diff --git a/Marco.Pms.Helpers/CacheHelper/ProjectCache.cs b/Marco.Pms.Helpers/CacheHelper/ProjectCache.cs
index bee37af..ec5598b 100644
--- a/Marco.Pms.Helpers/CacheHelper/ProjectCache.cs
+++ b/Marco.Pms.Helpers/CacheHelper/ProjectCache.cs
@@ -407,10 +407,19 @@ namespace Marco.Pms.Helpers
 
         #region=================================================================== WorkItem Cache Helper ===================================================================
 
-        public async Task<List<WorkItemMongoDB>> GetWorkItemsByWorkAreaIdsFromCache(List<Guid> workAreaIds)
+        public async Task<List<WorkItemMongoDB>> GetWorkItemsByWorkAreaIdsFromCache(List<Guid> workAreaIds, List<Guid> serviceIds)
         {
             var stringWorkAreaIds = workAreaIds.Select(wa => wa.ToString()).ToList();
-            var filter = Builders<WorkItemMongoDB>.Filter.In(w => w.WorkAreaId, stringWorkAreaIds);
+
+            var filterBuilder = Builders<WorkItemMongoDB>.Filter;
+            var filter = filterBuilder.Empty;
+
+            filter &= filterBuilder.In(w => w.WorkAreaId, stringWorkAreaIds);
+            if (serviceIds.Any())
+            {
+                var stringServiceIds = serviceIds.Select(s => s.ToString()).ToList();
+                filter &= filterBuilder.In(w => w.ActivityMaster!.ActivityGroupMaster!.Service!.Id, stringServiceIds);
+            }
 
             var workItems = await _taskCollection // replace with your actual collection name
                 .Find(filter)
@@ -449,9 +458,17 @@ namespace Marco.Pms.Helpers
                 }
             }
         }
-        public async Task<List<WorkItemMongoDB>> GetWorkItemDetailsByWorkAreaFromCache(Guid workAreaId)
+        public async Task<List<WorkItemMongoDB>> GetWorkItemDetailsByWorkAreaFromCache(Guid workAreaId, List<Guid> serviceIds)
         {
-            var filter = Builders<WorkItemMongoDB>.Filter.Eq(p => p.WorkAreaId, workAreaId.ToString());
+            var filterBuilder = Builders<WorkItemMongoDB>.Filter;
+            var filter = filterBuilder.Empty;
+
+            filter &= filterBuilder.Eq(p => p.WorkAreaId, workAreaId.ToString());
+            if (serviceIds.Any())
+            {
+                var stringServiceIds = serviceIds.Select(s => s.ToString()).ToList();
+                filter &= filterBuilder.In(w => w.ActivityMaster!.ActivityGroupMaster!.Service!.Id, stringServiceIds);
+            }
 
             var options = new UpdateOptions { IsUpsert = true };
             var workItems = await _taskCollection
diff --git a/Marco.Pms.Model/MongoDBModels/Masters/ActivityGroupMasterMongoDB.cs b/Marco.Pms.Model/MongoDBModels/Masters/ActivityGroupMasterMongoDB.cs
new file mode 100644
index 0000000..1b3169b
--- /dev/null
+++ b/Marco.Pms.Model/MongoDBModels/Masters/ActivityGroupMasterMongoDB.cs
@@ -0,0 +1,10 @@
+namespace Marco.Pms.Model.MongoDBModels.Masters
+{
+    public class ActivityGroupMasterMongoDB
+    {
+        public string Id { get; set; } = string.Empty;
+        public string Name { get; set; } = string.Empty;
+        public string Description { get; set; } = string.Empty;
+        public ServiceMasterMongoDB? Service { get; set; }
+    }
+}
diff --git a/Marco.Pms.Model/MongoDBModels/Masters/ServiceMasterMongoDB.cs b/Marco.Pms.Model/MongoDBModels/Masters/ServiceMasterMongoDB.cs
new file mode 100644
index 0000000..008b745
--- /dev/null
+++ b/Marco.Pms.Model/MongoDBModels/Masters/ServiceMasterMongoDB.cs
@@ -0,0 +1,9 @@
+namespace Marco.Pms.Model.MongoDBModels.Masters
+{
+    public class ServiceMasterMongoDB
+    {
+        public string Id { get; set; } = string.Empty;
+        public string Name { get; set; } = string.Empty;
+        public string Description { get; set; } = string.Empty;
+    }
+}
diff --git a/Marco.Pms.Model/MongoDBModels/Project/ActivityMasterMongoDB.cs b/Marco.Pms.Model/MongoDBModels/Project/ActivityMasterMongoDB.cs
index ecb88c1..becb30f 100644
--- a/Marco.Pms.Model/MongoDBModels/Project/ActivityMasterMongoDB.cs
+++ b/Marco.Pms.Model/MongoDBModels/Project/ActivityMasterMongoDB.cs
@@ -1,9 +1,12 @@
-namespace Marco.Pms.Model.MongoDBModels.Project
+using Marco.Pms.Model.MongoDBModels.Masters;
+
+namespace Marco.Pms.Model.MongoDBModels.Project
 {
     public class ActivityMasterMongoDB
     {
         public string Id { get; set; } = string.Empty;
         public string? ActivityName { get; set; }
         public string? UnitOfMeasurement { get; set; }
+        public ActivityGroupMasterMongoDB? ActivityGroupMaster { get; set; }
     }
 }
diff --git a/Marco.Pms.Model/ViewModels/Master/ActivityGroupDetailsListVM.cs b/Marco.Pms.Model/ViewModels/Master/ActivityGroupDetailsListVM.cs
new file mode 100644
index 0000000..dc84e2e
--- /dev/null
+++ b/Marco.Pms.Model/ViewModels/Master/ActivityGroupDetailsListVM.cs
@@ -0,0 +1,14 @@
+using Marco.Pms.Model.ViewModels.Activities;
+
+namespace Marco.Pms.Model.ViewModels.Master
+{
+    public class ActivityGroupDetailsListVM
+    {
+        public Guid Id { get; set; }
+        public string? Name { get; set; }
+        public string? Description { get; set; }
+        public bool IsSystem { get; set; }
+        public bool IsActive { get; set; }
+        public List<ActivityVM>? Activities { get; set; }
+    }
+}
diff --git a/Marco.Pms.Model/ViewModels/Master/ServiceDetailsListVM.cs b/Marco.Pms.Model/ViewModels/Master/ServiceDetailsListVM.cs
new file mode 100644
index 0000000..5181ea1
--- /dev/null
+++ b/Marco.Pms.Model/ViewModels/Master/ServiceDetailsListVM.cs
@@ -0,0 +1,12 @@
+namespace Marco.Pms.Model.ViewModels.Master
+{
+    public class ServiceDetailsListVM
+    {
+        public Guid Id { get; set; }
+        public string? Name { get; set; }
+        public string? Description { get; set; }
+        public bool IsSystem { get; set; }
+        public bool IsActive { get; set; }
+        public List<ActivityGroupDetailsListVM>? ActivityGroups { get; set; }
+    }
+}
diff --git a/Marco.Pms.Services/Controllers/MasterController.cs b/Marco.Pms.Services/Controllers/MasterController.cs
index 17d0620..393d423 100644
--- a/Marco.Pms.Services/Controllers/MasterController.cs
+++ b/Marco.Pms.Services/Controllers/MasterController.cs
@@ -2,12 +2,10 @@
 using Marco.Pms.Model.Dtos.Activities;
 using Marco.Pms.Model.Dtos.DocumentManager;
 using Marco.Pms.Model.Dtos.Master;
-using Marco.Pms.Model.Entitlements;
 using Marco.Pms.Model.Forum;
 using Marco.Pms.Model.Mapper;
 using Marco.Pms.Model.Master;
 using Marco.Pms.Model.Utilities;
-using Marco.Pms.Model.ViewModels.Activities;
 using Marco.Pms.Model.ViewModels.Forum;
 using Marco.Pms.Model.ViewModels.Master;
 using Marco.Pms.Services.Service.ServiceInterfaces;
@@ -96,6 +94,14 @@ namespace Marco.Pms.Services.Controllers
             return StatusCode(response.StatusCode, response);
         }
 
+        [HttpGet("service/all/list")]
+        public async Task<IActionResult> GetServiceDetailsList([FromQuery] Guid? serviceId)
+        {
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.GetServiceDetailsListAsync(serviceId, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
+        }
+
         [HttpPost("service/create")]
         public async Task<IActionResult> CreateService([FromBody] ServiceMasterDto serviceMasterDto)
         {
@@ -125,10 +131,10 @@ namespace Marco.Pms.Services.Controllers
         #region =================================================================== Activity Group APIs ===================================================================
 
         [HttpGet("activity-group/list")]
-        public async Task<IActionResult> GetActivityGroups()
+        public async Task<IActionResult> GetActivityGroups([FromQuery] Guid? serviceId)
         {
             var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
-            var response = await _masterService.GetActivityGroupsAsync(loggedInEmployee, tenantId);
+            var response = await _masterService.GetActivityGroupsAsync(serviceId, loggedInEmployee, tenantId);
             return StatusCode(response.StatusCode, response);
         }
 
@@ -162,152 +168,35 @@ namespace Marco.Pms.Services.Controllers
 
         [HttpGet]
         [Route("activities")]
-        public async Task<IActionResult> GetActivitiesMaster()
+        public async Task<IActionResult> GetActivitiesMaster([FromQuery] Guid? activityGroupId)
         {
-            Guid tenantId = _userHelper.GetTenantId();
-            var activities = await _context.ActivityMasters.Where(c => c.TenantId == tenantId && c.IsActive == true).ToListAsync();
-            List<ActivityVM> activitiesVM = new List<ActivityVM>();
-            foreach (var activity in activities)
-            {
-                var checkList = await _context.ActivityCheckLists.Where(c => c.TenantId == tenantId && c.ActivityId == activity.Id).ToListAsync();
-                List<CheckListVM> checkListVM = new List<CheckListVM>();
-                if (checkList != null)
-                {
-                    foreach (ActivityCheckList check in checkList)
-                    {
-                        var checkVM = check.ToCheckListVMFromActivityCheckList(activity.Id, false);
-                        checkListVM.Add(checkVM);
-                    }
-                }
-
-                ActivityVM activityVM = activity.ToActivityVMFromActivityMaster(checkListVM);
-                activitiesVM.Add(activityVM);
-            }
-            _logger.LogInfo("{count} activity records fetched successfully from tenant {tenantId}", activitiesVM.Count, tenantId);
-            return Ok(ApiResponse<object>.SuccessResponse(activitiesVM, System.String.Format("{0} activity records fetched successfully", activitiesVM.Count), 200));
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.GetActivitiesMasterAsync(activityGroupId, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
         }
 
         [HttpPost("activity")]
         public async Task<IActionResult> CreateActivity([FromBody] CreateActivityMasterDto createActivity)
         {
-            Guid tenantId = _userHelper.GetTenantId();
-            var employee = await _userHelper.GetCurrentEmployeeAsync();
-            if (employee.TenantId != tenantId)
-            {
-                _logger.LogWarning("User from tenant {employeeTenantId} tries to access data from tenant {tenantId}", employee.TenantId ?? Guid.Empty, tenantId);
-                return Unauthorized(ApiResponse<object>.ErrorResponse("Current tenant did not match with user's tenant", "Current tenant did not match with user's tenant", 401));
-            }
-            var activityMaster = createActivity.ToActivityMasterFromCreateActivityMasterDto(tenantId);
-            _context.ActivityMasters.Add(activityMaster);
-            await _context.SaveChangesAsync();
-            List<CheckListVM> checkListVM = new List<CheckListVM>();
-
-            if (createActivity.CheckList != null)
-            {
-                List<ActivityCheckList> activityCheckList = new List<ActivityCheckList>();
-                foreach (var check in createActivity.CheckList)
-                {
-                    ActivityCheckList checkList = check.ToActivityCheckListFromCreateCheckListDto(tenantId, activityMaster.Id);
-                    activityCheckList.Add(checkList);
-                }
-                _context.ActivityCheckLists.AddRange(activityCheckList);
-                await _context.SaveChangesAsync();
-
-                foreach (ActivityCheckList check in activityCheckList)
-                {
-                    var checkVM = check.ToCheckListVMFromActivityCheckList(activityMaster.Id, false);
-                    checkListVM.Add(checkVM);
-                }
-            }
-            ActivityVM activityVM = activityMaster.ToActivityVMFromActivityMaster(checkListVM);
-
-            _logger.LogInfo("activity created successfully from tenant {tenantId}", tenantId);
-            return Ok(ApiResponse<object>.SuccessResponse(activityVM, "activity created successfully", 200));
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.CreateActivityAsync(createActivity, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
         }
 
         [HttpPost("activity/edit/{id}")]
         public async Task<IActionResult> UpdateActivity(Guid id, [FromBody] CreateActivityMasterDto createActivity)
         {
-            Guid tenantId = _userHelper.GetTenantId();
-            var employee = await _userHelper.GetCurrentEmployeeAsync();
-            ActivityMaster? activity = await _context.ActivityMasters.FirstOrDefaultAsync(x => x.Id == id && x.IsActive == true && x.TenantId == tenantId);
-            if (activity != null && createActivity.UnitOfMeasurement != null && createActivity.ActivityName != null)
-            {
-
-                activity.ActivityName = createActivity.ActivityName;
-                activity.UnitOfMeasurement = createActivity.UnitOfMeasurement;
-                List<ActivityCheckList> activityCheckLists = await _context.ActivityCheckLists.AsNoTracking().Where(c => c.ActivityId == activity.Id).ToListAsync();
-                List<CheckListVM> checkListVM = new List<CheckListVM>();
-
-                if (createActivity.CheckList != null)
-                {
-
-                    var newCheckIds = createActivity.CheckList.Select(c => c.Id);
-
-                    List<ActivityCheckList> updateCheckList = new List<ActivityCheckList>();
-                    List<ActivityCheckList> deleteCheckList = new List<ActivityCheckList>();
-                    if (newCheckIds.Contains(null))
-                    {
-                        foreach (var check in createActivity.CheckList)
-                        {
-                            if (check.Id == null)
-                            {
-                                ActivityCheckList checkList = check.ToActivityCheckListFromCreateCheckListDto(tenantId, activity.Id);
-                                updateCheckList.Add(checkList);
-                            }
-                        }
-                    }
-                    foreach (var check in activityCheckLists)
-                    {
-                        if (newCheckIds.Contains(check.Id))
-                        {
-                            var updatedCheck = createActivity.CheckList.Find(c => c.Id == check.Id);
-                            ActivityCheckList checkList = updatedCheck != null ? updatedCheck.ToActivityCheckListFromCreateCheckListDto(tenantId, activity.Id) : new ActivityCheckList();
-                            updateCheckList.Add(checkList);
-                        }
-                        else
-                        {
-                            deleteCheckList.Add(check);
-                        }
-                    }
-                    _context.ActivityCheckLists.UpdateRange(updateCheckList);
-                    if (deleteCheckList != null)
-                    {
-                        _context.ActivityCheckLists.RemoveRange(deleteCheckList);
-                    }
-                    await _context.SaveChangesAsync();
-
-                    foreach (ActivityCheckList check in updateCheckList)
-                    {
-                        var checkVM = check.ToCheckListVMFromActivityCheckList(activity.Id, false);
-                        checkListVM.Add(checkVM);
-                    }
-                }
-                else if (activityCheckLists != null)
-                {
-                    _context.ActivityCheckLists.RemoveRange(activityCheckLists);
-                    await _context.SaveChangesAsync();
-                }
-                ActivityVM activityVM = activity.ToActivityVMFromActivityMaster(checkListVM);
-                _logger.LogInfo("activity updated successfully from tenant {tenantId}", tenantId);
-                return Ok(ApiResponse<object>.SuccessResponse(activityVM, "activity updated successfully", 200));
-            }
-            _logger.LogWarning("Activity {ActivityId} not found", id);
-            return NotFound(ApiResponse<object>.ErrorResponse("Activity not found", "Activity not found", 404));
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.UpdateActivityAsync(id, createActivity, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
         }
 
         [HttpDelete("activity/delete/{id}")]
-        public async Task<IActionResult> DeleteActivity(Guid Id)
+        public async Task<IActionResult> DeleteActivity(Guid id, [FromQuery] bool active = false)
         {
-            Guid tenantId = _userHelper.GetTenantId();
-            var activity = await _context.ActivityMasters.FirstOrDefaultAsync(a => a.Id == Id && a.TenantId == tenantId);
-            if (activity != null)
-            {
-                activity.IsActive = false;
-            }
-            await _context.SaveChangesAsync();
-            _logger.LogInfo("Activity Deleted Successfully from tenant {tenantId}", tenantId);
-            return Ok(ApiResponse<object>.SuccessResponse(new { }, "Activity Deleted Successfully", 200));
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.DeleteActivityAsync(id, active, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
         }
 
         #endregion
diff --git a/Marco.Pms.Services/Controllers/ProjectController.cs b/Marco.Pms.Services/Controllers/ProjectController.cs
index ea230e8..c48cc5f 100644
--- a/Marco.Pms.Services/Controllers/ProjectController.cs
+++ b/Marco.Pms.Services/Controllers/ProjectController.cs
@@ -342,7 +342,7 @@ namespace MarcoBMS.Services.Controllers
         }
 
         [HttpGet("tasks/{workAreaId}")]
-        public async Task<IActionResult> GetWorkItems(Guid workAreaId)
+        public async Task<IActionResult> GetWorkItems(Guid workAreaId, [FromQuery] Guid? serviceId)
         {
             // --- Step 1: Input Validation ---
             if (!ModelState.IsValid)
@@ -354,7 +354,7 @@ namespace MarcoBMS.Services.Controllers
 
             // --- Step 2: Prepare data without I/O ---
             Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
-            var response = await _projectServices.GetWorkItemsAsync(workAreaId, tenantId, loggedInEmployee);
+            var response = await _projectServices.GetWorkItemsAsync(workAreaId, serviceId, tenantId, loggedInEmployee);
             return StatusCode(response.StatusCode, response);
         }
         [HttpGet("tasks-employee/{employeeId}")]
diff --git a/Marco.Pms.Services/Helpers/CacheUpdateHelper.cs b/Marco.Pms.Services/Helpers/CacheUpdateHelper.cs
index 60005ab..3584c8e 100644
--- a/Marco.Pms.Services/Helpers/CacheUpdateHelper.cs
+++ b/Marco.Pms.Services/Helpers/CacheUpdateHelper.cs
@@ -599,11 +599,11 @@ namespace Marco.Pms.Services.Helpers
 
         #region ======================================================= WorkItem Cache =======================================================
 
-        public async Task<List<WorkItemMongoDB>?> GetWorkItemsByWorkAreaIds(List<Guid> workAreaIds)
+        public async Task<List<WorkItemMongoDB>?> GetWorkItemsByWorkAreaIds(List<Guid> workAreaIds, List<Guid> serviceIds)
         {
             try
             {
-                var response = await _projectCache.GetWorkItemsByWorkAreaIdsFromCache(workAreaIds);
+                var response = await _projectCache.GetWorkItemsByWorkAreaIdsFromCache(workAreaIds, serviceIds);
                 if (response.Count > 0)
                 {
                     return response;
@@ -640,11 +640,11 @@ namespace Marco.Pms.Services.Helpers
                 _logger.LogWarning("Error occured while saving workItems form Cache: {Error}", ex.Message);
             }
         }
-        public async Task<List<WorkItemMongoDB>?> GetWorkItemDetailsByWorkArea(Guid workAreaId)
+        public async Task<List<WorkItemMongoDB>?> GetWorkItemDetailsByWorkArea(Guid workAreaId, List<Guid> serviceIds)
         {
             try
             {
-                var workItems = await _projectCache.GetWorkItemDetailsByWorkAreaFromCache(workAreaId);
+                var workItems = await _projectCache.GetWorkItemDetailsByWorkAreaFromCache(workAreaId, serviceIds);
                 if (workItems.Count > 0)
                 {
                     return workItems;
diff --git a/Marco.Pms.Services/Helpers/GeneralHelper.cs b/Marco.Pms.Services/Helpers/GeneralHelper.cs
index 289c87e..c983b84 100644
--- a/Marco.Pms.Services/Helpers/GeneralHelper.cs
+++ b/Marco.Pms.Services/Helpers/GeneralHelper.cs
@@ -141,8 +141,11 @@ namespace Marco.Pms.Services.Helpers
                 // Task 1: Fetch the WorkItem entities and their related data.
                 var workItemsTask = _context.WorkItems
                     .Include(wi => wi.ActivityMaster)
+                        .ThenInclude(am => am!.ActivityGroup)
+                            .ThenInclude(ag => ag!.Service)
                     .Include(wi => wi.WorkCategoryMaster)
-                    .Where(wi => wi.WorkAreaId == workAreaId)
+                    .Where(wi => wi.WorkAreaId == workAreaId && wi.ActivityMaster != null && wi.ActivityMaster.ActivityGroup != null
+                    && wi.ActivityMaster.ActivityGroup.Service != null && wi.WorkCategoryMaster != null)
                     .AsNoTracking()
                     .ToListAsync();
 
@@ -189,7 +192,19 @@ namespace Marco.Pms.Services.Helpers
                     {
                         Id = wi.ActivityMaster.Id.ToString(),
                         ActivityName = wi.ActivityMaster.ActivityName,
-                        UnitOfMeasurement = wi.ActivityMaster.UnitOfMeasurement
+                        UnitOfMeasurement = wi.ActivityMaster.UnitOfMeasurement,
+                        ActivityGroupMaster = new ActivityGroupMasterMongoDB
+                        {
+                            Id = wi.ActivityMaster.ActivityGroup!.Id.ToString(),
+                            Name = wi.ActivityMaster.ActivityGroup.Name,
+                            Description = wi.ActivityMaster.ActivityGroup.Description,
+                            Service = new ServiceMasterMongoDB
+                            {
+                                Id = wi.ActivityMaster.ActivityGroup.Service!.Id.ToString(),
+                                Name = wi.ActivityMaster.ActivityGroup.Service.Name,
+                                Description = wi.ActivityMaster.ActivityGroup.Service.Description
+                            }
+                        }
                     } : null,
                     WorkCategoryMaster = wi.WorkCategoryMaster != null ? new WorkCategoryMasterMongoDB
                     {
diff --git a/Marco.Pms.Services/Helpers/ReportHelper.cs b/Marco.Pms.Services/Helpers/ReportHelper.cs
index 5a174e6..49c3000 100644
--- a/Marco.Pms.Services/Helpers/ReportHelper.cs
+++ b/Marco.Pms.Services/Helpers/ReportHelper.cs
@@ -148,7 +148,7 @@ namespace Marco.Pms.Services.Helpers
                 var areaIds = areas.Select(a => Guid.Parse(a.Id)).ToList();
 
                 // fetch Work Items
-                workItems = await _cache.GetWorkItemsByWorkAreaIds(areaIds);
+                workItems = await _cache.GetWorkItemsByWorkAreaIds(areaIds, new List<Guid>());
                 if (workItems == null || !workItems.Any())
                 {
                     workItems = await _context.WorkItems
diff --git a/Marco.Pms.Services/MappingProfiles/MappingProfile.cs b/Marco.Pms.Services/MappingProfiles/MappingProfile.cs
index 4df070b..aa79f33 100644
--- a/Marco.Pms.Services/MappingProfiles/MappingProfile.cs
+++ b/Marco.Pms.Services/MappingProfiles/MappingProfile.cs
@@ -269,7 +269,7 @@ namespace Marco.Pms.Services.MappingProfiles
 
             #region ======================================================= Activity Group Master =======================================================
 
-            CreateMap<ServiceMasterDto, ActivityGroupMaster>()
+            CreateMap<ActivityGroupDto, ActivityGroupMaster>()
                 .ForMember(
                     dest => dest.Id,
                     // Explicitly and safely convert nullable Guid to non-nullable Guid
diff --git a/Marco.Pms.Services/Service/MasterService.cs b/Marco.Pms.Services/Service/MasterService.cs
index f8a9a73..1fae12b 100644
--- a/Marco.Pms.Services/Service/MasterService.cs
+++ b/Marco.Pms.Services/Service/MasterService.cs
@@ -261,6 +261,118 @@ namespace Marco.Pms.Services.Service
                 return ApiResponse<object>.ErrorResponse("An error occurred while fetching services", ex.Message, 500);
             }
         }
+
+        /// <summary>
+        /// Asynchronously retrieves a structured list of services, their activity groups, activities, and associated checklists for a specific tenant.
+        /// This method fetches data in multiple steps and processes it in-memory, preserving the original business logic.
+        /// </summary>
+        /// <param name="loggedInEmployee">The employee currently logged in. This parameter is available for future authorization or logging extensions.</param>
+        /// <param name="tenantId">The unique identifier of the tenant for which to retrieve the data.</param>
+        /// <returns>An ApiResponse containing a list of ServiceDetailsListVM or an error message in case of failure.</returns>
+        public async Task<ApiResponse<object>> GetServiceDetailsListAsync(Guid? serviceId, Employee loggedInEmployee, Guid tenantId)
+        {
+            // Log the initiation of the request with structured parameters for better traceability.
+            _logger.LogInfo("Attempting to fetch service details list for TenantId: {TenantId}", tenantId);
+
+            try
+            {
+                // --- Step 1: Fetch all relevant activities for the tenant ---
+                // This query retrieves all active 'ActivityMaster' records for the given tenant that are properly linked to an ActivityGroup and a Service.
+                // Eager loading (.Include/.ThenInclude) is used to bring in related ActivityGroup and Service entities to prevent N+1 query problems later.
+                var activityQuery = _context.ActivityMasters
+                    .Include(a => a.ActivityGroup)
+                        .ThenInclude(ag => ag!.Service)
+                    .Where(a => a.TenantId == tenantId && a.IsActive);
+
+                if (serviceId.HasValue)
+                {
+                    activityQuery = activityQuery.Where(a => a.ActivityGroup != null && a.ActivityGroup.Service != null && a.ActivityGroup.Service.Id == serviceId);
+                }
+
+                var activities = await activityQuery
+                    .ToListAsync();
+
+                _logger.LogInfo("Step 1 complete: Fetched {ActivityCount} activities for TenantId: {TenantId}", activities.Count, tenantId);
+
+                // --- Step 2: Fetch all checklists related to the retrieved activities ---
+                // To avoid fetching all checklists in the database, we first collect the IDs of the activities from the previous step.
+                var activityIds = activities.Select(a => a.Id).ToList();
+
+                // This second database query fetches only the 'ActivityCheckList' records associated with the relevant activities.
+                var checkLists = await _context.ActivityCheckLists
+                    .Where(c => c.TenantId == tenantId && activityIds.Contains(c.ActivityId))
+                    .ToListAsync();
+
+                _logger.LogInfo("Step 2 complete: Fetched {ChecklistCount} checklists for TenantId: {TenantId}", checkLists.Count, tenantId);
+
+                // --- Step 3: Group checklists by activity in memory for efficient lookup ---
+                // To quickly find all checklists for a given activity, we group the flat list of checklists into a dictionary.
+                // The key is the ActivityId, and the value is the list of associated checklists.
+                var groupedChecklists = checkLists
+                    .GroupBy(c => c.ActivityId)
+                    .ToDictionary(g => g.Key, g => g.ToList());
+
+                // --- Step 4: Build the hierarchical ViewModel structure in memory ---
+                // First, get distinct lists of services and activity groups from the already fetched 'activities' collection.
+                var services = activities.Select(a => a.ActivityGroup!.Service!).Distinct().ToList();
+                var activityGroupList = activities.Select(a => a.ActivityGroup!).Distinct().ToList();
+
+                // Now, construct the final nested ViewModel.
+                // This part iterates through the distinct services and builds the response object by filtering the in-memory collections.
+                List<ServiceDetailsListVM> Vm = services.Select(s =>
+                {
+                    var response = new ServiceDetailsListVM
+                    {
+                        Id = s.Id,
+                        Name = s.Name,
+                        Description = s.Description,
+                        IsActive = s.IsActive,
+                        IsSystem = s.IsSystem,
+                        ActivityGroups = activityGroupList
+                            .Where(ag => ag.ServiceId == s.Id) // Find groups for the current service
+                            .Select(ag => new ActivityGroupDetailsListVM
+                            {
+                                Id = ag.Id,
+                                Name = ag.Name,
+                                Description = ag.Description,
+                                IsActive = ag.IsActive,
+                                IsSystem = ag.IsSystem,
+                                Activities = activities
+                                    .Where(a => a.ActivityGroupId == ag.Id) // Find activities for the current group
+                                    .Select(a =>
+                                    {
+                                        // Retrieve the checklists for the current activity from our dictionary lookup.
+                                        var checklistForActivity = groupedChecklists.ContainsKey(a.Id)
+                                            ? groupedChecklists[a.Id]
+                                            : new List<ActivityCheckList>();
+
+                                        return new ActivityVM
+                                        {
+                                            Id = a.Id,
+                                            ActivityName = a.ActivityName,
+                                            UnitOfMeasurement = a.UnitOfMeasurement,
+                                            // BUG FIX: Correctly mapping properties from the activity ('a') itself, not the parent service ('s').
+                                            IsActive = a.IsActive,
+                                            IsSystem = a.IsSystem,
+                                            CheckLists = _mapper.Map<List<CheckListVM>>(checklistForActivity)
+                                        };
+                                    }).ToList()
+                            }).ToList()
+                    };
+                    return response;
+                }).ToList();
+
+                _logger.LogInfo("Successfully processed and mapped {ServiceCount} services for TenantId: {TenantId}", Vm.Count, tenantId);
+
+                return ApiResponse<object>.SuccessResponse(Vm, "Service details list fetched successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                // If any part of the process fails, log the detailed exception and return a standardized error response.
+                _logger.LogError(ex, "An error occurred while fetching service details for TenantId: {TenantId}", tenantId);
+                return ApiResponse<object>.ErrorResponse("An internal server error occurred while fetching service details.", 500);
+            }
+        }
         public async Task<ApiResponse<object>> CreateServiceAsync(ServiceMasterDto serviceMasterDto, Employee loggedInEmployee, Guid tenantId)
         {
             _logger.LogInfo("CreateService called with Name: {ServiceName}", serviceMasterDto.Name);
@@ -407,16 +519,23 @@ namespace Marco.Pms.Services.Service
 
         #region =================================================================== Activity Group APIs ===================================================================
 
-        public async Task<ApiResponse<object>> GetActivityGroupsAsync(Employee loggedInEmployee, Guid tenantId)
+        public async Task<ApiResponse<object>> GetActivityGroupsAsync(Guid? serviceId, Employee loggedInEmployee, Guid tenantId)
         {
             _logger.LogInfo("GetActivityGroups called");
 
             try
             {
                 // Step 1: Fetch all activity groups for the tenant
-                var activityGroups = await _context.ActivityGroupMasters
+                var activityGroupQuery = _context.ActivityGroupMasters
                     .Include(ag => ag.Service)
-                    .Where(ag => ag.TenantId == tenantId && ag.IsActive)
+                    .Where(ag => ag.TenantId == tenantId && ag.IsActive);
+
+                if (serviceId.HasValue)
+                {
+                    activityGroupQuery = activityGroupQuery.Where(ag => ag.ServiceId == serviceId);
+                }
+
+                var activityGroups = await activityGroupQuery
                     .Select(ag => _mapper.Map<ActivityGroupMasterVM>(ag))
                     .ToListAsync();
 
@@ -586,17 +705,25 @@ namespace Marco.Pms.Services.Service
         #endregion
 
         #region =================================================================== Activity APIs ===================================================================
-        public async Task<ApiResponse<object>> GetActivitiesMasterAsync(Employee loggedInEmployee, Guid tenantId)
+        public async Task<ApiResponse<object>> GetActivitiesMasterAsync(Guid? activityGroupId, Employee loggedInEmployee, Guid tenantId)
         {
             _logger.LogInfo("GetActivitiesMaster called");
 
             try
             {
                 // Step 1: Fetch all active activities for the tenant
-                var activities = await _context.ActivityMasters
+
+                var activityQuery = _context.ActivityMasters
                     .Include(c => c.ActivityGroup)
                         .ThenInclude(ag => ag!.Service)
-                    .Where(c => c.TenantId == tenantId && c.IsActive)
+                    .Where(c => c.TenantId == tenantId && c.IsActive);
+
+                if (activityGroupId.HasValue)
+                {
+                    activityQuery = activityQuery.Where(a => a.ActivityGroupId == activityGroupId);
+                }
+
+                var activities = await activityQuery
                     .ToListAsync();
 
                 if (activities.Count == 0)
diff --git a/Marco.Pms.Services/Service/ProjectServices.cs b/Marco.Pms.Services/Service/ProjectServices.cs
index ab72c8e..f88516c 100644
--- a/Marco.Pms.Services/Service/ProjectServices.cs
+++ b/Marco.Pms.Services/Service/ProjectServices.cs
@@ -1160,7 +1160,7 @@ namespace Marco.Pms.Services.Service
         /// <param name="tenantId">The ID of the current tenant.</param>
         /// <param name="loggedInEmployee">The current authenticated employee for permission checks.</param>
         /// <returns>An ApiResponse containing a list of work items or an error.</returns>
-        public async Task<ApiResponse<object>> GetWorkItemsAsync(Guid workAreaId, Guid tenantId, Employee loggedInEmployee)
+        public async Task<ApiResponse<object>> GetWorkItemsAsync(Guid workAreaId, Guid? serviceId, Guid tenantId, Employee loggedInEmployee)
         {
             _logger.LogInfo("GetWorkItems called for WorkAreaId: {WorkAreaId} by User: {UserId}", workAreaId, loggedInEmployee.Id);
 
@@ -1170,8 +1170,78 @@ namespace Marco.Pms.Services.Service
             try
             {
                 var _permission = scope.ServiceProvider.GetRequiredService<PermissionServices>();
+
+                var projectId = await _context.WorkAreas
+                   .Where(wa => wa.Id == workAreaId && wa.TenantId == tenantId && wa.Floor != null && wa.Floor.Building != null)
+                   .Select(wa => wa.Floor!.Building!.ProjectId)
+                   .FirstOrDefaultAsync();
+
+                if (projectId == Guid.Empty)
+                {
+                    _logger.LogWarning("Work Area not found for WorkAreaId: {WorkAreaId}", workAreaId);
+                    return ApiResponse<object>.ErrorResponse("Not Found", $"Work Area with ID {workAreaId} not found.", 404);
+                }
+
+                var project = await _context.Projects.FirstOrDefaultAsync(p => p.Id == projectId && p.TenantId == tenantId);
+                if (project == null)
+                {
+                    return ApiResponse<object>.ErrorResponse("Project not found", "Project not found in database", 404);
+                }
+
+                var hasProjectAccessTask = Task.Run(async () =>
+                {
+                    using var taskScope = _serviceScopeFactory.CreateScope();
+                    var permission = taskScope.ServiceProvider.GetRequiredService<PermissionServices>();
+                    return await permission.HasProjectPermission(loggedInEmployee, projectId);
+                });
+                var hasGenericViewInfraPermissionTask = Task.Run(async () =>
+                {
+                    using var taskScope = _serviceScopeFactory.CreateScope();
+                    var permission = taskScope.ServiceProvider.GetRequiredService<PermissionServices>();
+                    return await permission.HasPermission(PermissionsMaster.ViewProjectInfra, loggedInEmployee.Id, projectId);
+                });
+
+                await Task.WhenAll(hasProjectAccessTask, hasGenericViewInfraPermissionTask);
+
+                var hasProjectAccess = hasProjectAccessTask.Result;
+                var hasGenericViewInfraPermission = hasGenericViewInfraPermissionTask.Result;
+
+                if (!hasProjectAccess || !hasGenericViewInfraPermission)
+                {
+                    _logger.LogWarning("Access DENIED for user {UserId} on WorkAreaId {WorkAreaId}.", loggedInEmployee.Id, workAreaId);
+                    return ApiResponse<object>.ErrorResponse("Access Denied", "You do not have sufficient permissions to view these work items.", 403);
+                }
+
+                List<Guid> serviceIds = new List<Guid>();
+                if (!serviceId.HasValue)
+                {
+                    if (project.PromoterId == loggedInEmployee.OrganizationId && project.PMCId == loggedInEmployee.OrganizationId)
+                    {
+                        var projectServices = await _context.ProjectServiceMappings
+                            .Include(ps => ps.Service)
+                            .Where(ps => ps.ProjectId == projectId && ps.Service != null && ps.TenantId == tenantId && ps.IsActive)
+                            .ToListAsync();
+                        serviceIds = projectServices.Select(ps => ps.ServiceId).Distinct().ToList();
+                    }
+                    else
+                    {
+                        var orgProjectMapping = await _context.ProjectOrgMappings
+                            .Include(po => po.ProjectService)
+                                .ThenInclude(ps => ps!.Service)
+                            .Where(po => po.OrganizationId == loggedInEmployee.OrganizationId && po.ProjectService != null
+                            && po.ProjectService.IsActive && po.ProjectService.ProjectId == projectId && po.ProjectService.Service != null)
+                            .ToListAsync();
+
+                        serviceIds = orgProjectMapping.Select(po => po.ProjectService!.ServiceId).Distinct().ToList();
+                    }
+                }
+                else
+                {
+                    serviceIds.Add(serviceId.Value);
+                }
+
                 // --- Step 1: Cache-First Strategy ---
-                var cachedWorkItems = await _cache.GetWorkItemDetailsByWorkArea(workAreaId);
+                var cachedWorkItems = await _cache.GetWorkItemDetailsByWorkArea(workAreaId, serviceIds);
                 if (cachedWorkItems != null)
                 {
                     _logger.LogInfo("Cache HIT for WorkAreaId: {WorkAreaId}. Returning {Count} items from cache.", workAreaId, cachedWorkItems.Count);
@@ -1180,28 +1250,6 @@ namespace Marco.Pms.Services.Service
 
                 _logger.LogInfo("Cache MISS for WorkAreaId: {WorkAreaId}. Fetching from database.", workAreaId);
 
-                // --- Step 2: Security Check First ---
-                // This pattern remains the most robust: verify permissions before fetching a large list.
-                var projectInfo = await _context.WorkAreas
-                    .Where(wa => wa.Id == workAreaId && wa.TenantId == tenantId && wa.Floor != null && wa.Floor.Building != null)
-                    .Select(wa => new { wa.Floor!.Building!.ProjectId })
-                    .FirstOrDefaultAsync();
-
-                if (projectInfo == null)
-                {
-                    _logger.LogWarning("Work Area not found for WorkAreaId: {WorkAreaId}", workAreaId);
-                    return ApiResponse<object>.ErrorResponse("Not Found", $"Work Area with ID {workAreaId} not found.", 404);
-                }
-
-                var hasProjectAccess = await _permission.HasProjectPermission(loggedInEmployee, projectInfo.ProjectId);
-                var hasGenericViewInfraPermission = await _permission.HasPermission(PermissionsMaster.ViewProjectInfra, loggedInEmployee.Id, projectInfo.ProjectId);
-
-                if (!hasProjectAccess || !hasGenericViewInfraPermission)
-                {
-                    _logger.LogWarning("Access DENIED for user {UserId} on WorkAreaId {WorkAreaId}.", loggedInEmployee.Id, workAreaId);
-                    return ApiResponse<object>.ErrorResponse("Access Denied", "You do not have sufficient permissions to view these work items.", 403);
-                }
-
                 // --- Step 3: Fetch Full Entities for Caching and Mapping ---
                 var workItemVMs = await _generalHelper.GetWorkItemsListFromDB(workAreaId);
 
@@ -1218,6 +1266,8 @@ namespace Marco.Pms.Services.Service
                     _logger.LogError(ex, "Background cache update failed for WorkAreaId: {WorkAreaId}", workAreaId);
                 }
 
+                var stringServiceIds = serviceIds.Select(s => s.ToString()).ToList();
+                workItemVMs = workItemVMs.Where(wi => stringServiceIds.Contains(wi.ActivityMaster!.ActivityGroupMaster!.Service!.Id)).ToList();
 
                 _logger.LogInfo("{Count} work items fetched successfully for WorkAreaId: {WorkAreaId}", workItemVMs.Count, workAreaId);
                 return ApiResponse<object>.SuccessResponse(workItemVMs, $"{workItemVMs.Count} tasks fetched successfully.", 200);
diff --git a/Marco.Pms.Services/Service/ServiceInterfaces/IMasterService.cs b/Marco.Pms.Services/Service/ServiceInterfaces/IMasterService.cs
index f79d62f..a53edb0 100644
--- a/Marco.Pms.Services/Service/ServiceInterfaces/IMasterService.cs
+++ b/Marco.Pms.Services/Service/ServiceInterfaces/IMasterService.cs
@@ -1,4 +1,5 @@
-using Marco.Pms.Model.Dtos.DocumentManager;
+using Marco.Pms.Model.Dtos.Activities;
+using Marco.Pms.Model.Dtos.DocumentManager;
 using Marco.Pms.Model.Dtos.Master;
 using Marco.Pms.Model.Employees;
 using Marco.Pms.Model.Utilities;
@@ -20,15 +21,26 @@ namespace Marco.Pms.Services.Service.ServiceInterfaces
         //Task<ApiResponse<object>> DeleteGlobalServiceAsync(Guid id, bool active, Employee loggedInEmployee, Guid tenantId);
 
         #endregion
+
         #region =================================================================== Service Master APIs ===================================================================
         Task<ApiResponse<object>> GetServicesAsync(Employee loggedInEmployee, Guid tenantId);
+        Task<ApiResponse<object>> GetServiceDetailsListAsync(Guid? serviceId, Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> CreateServiceAsync(ServiceMasterDto serviceMasterDto, Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> UpdateServiceAsync(Guid id, ServiceMasterDto serviceMasterDto, Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> DeleteServiceAsync(Guid id, bool active, Employee loggedInEmployee, Guid tenantId);
 
         #endregion
+
+        #region =================================================================== Activity APIs ===================================================================
+        Task<ApiResponse<object>> GetActivitiesMasterAsync(Guid? activityGroupId, Employee loggedInEmployee, Guid tenantId);
+        Task<ApiResponse<object>> CreateActivityAsync(CreateActivityMasterDto createActivity, Employee loggedInEmployee, Guid tenantId);
+        Task<ApiResponse<object>> UpdateActivityAsync(Guid id, CreateActivityMasterDto createActivity, Employee loggedInEmployee, Guid tenantId);
+        Task<ApiResponse<object>> DeleteActivityAsync(Guid id, bool isActive, Employee loggedInEmployee, Guid tenantId);
+
+        #endregion
+
         #region =================================================================== Activity Group Master APIs ===================================================================
-        Task<ApiResponse<object>> GetActivityGroupsAsync(Employee loggedInEmployee, Guid tenantId);
+        Task<ApiResponse<object>> GetActivityGroupsAsync(Guid? serviceId, Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> CreateActivityGroupAsync(ActivityGroupDto activityGroupDto, Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> UpdateActivityGroupAsync(Guid id, ActivityGroupDto activityGroupDto, Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> DeleteActivityGroupAsync(Guid id, bool isActive, Employee loggedInEmployee, Guid tenantId);
diff --git a/Marco.Pms.Services/Service/ServiceInterfaces/IProjectServices.cs b/Marco.Pms.Services/Service/ServiceInterfaces/IProjectServices.cs
index 6d06559..7679d95 100644
--- a/Marco.Pms.Services/Service/ServiceInterfaces/IProjectServices.cs
+++ b/Marco.Pms.Services/Service/ServiceInterfaces/IProjectServices.cs
@@ -25,7 +25,7 @@ namespace Marco.Pms.Services.Service.ServiceInterfaces
         Task<ApiResponse<object>> GetProjectByEmployeeBasicAsync(Guid employeeId, Guid tenantId, Employee loggedInEmployee);
 
         Task<ApiResponse<object>> GetInfraDetailsAsync(Guid projectId, Guid tenantId, Employee loggedInEmployee);
-        Task<ApiResponse<object>> GetWorkItemsAsync(Guid workAreaId, Guid tenantId, Employee loggedInEmployee);
+        Task<ApiResponse<object>> GetWorkItemsAsync(Guid workAreaId, Guid? serviceId, Guid tenantId, Employee loggedInEmployee);
         Task<ApiResponse<object>> GetTasksByEmployeeAsync(Guid employeeId, DateTime fromDate, DateTime toDate, Guid tenantId, Employee loggedInEmployee);
         Task<ServiceResponse> ManageProjectInfraAsync(List<InfraDto> infraDtos, Guid tenantId, Employee loggedInEmployee);
         Task<ApiResponse<List<WorkItemVM>>> CreateProjectTaskAsync(List<WorkItemDto> workItemDtos, Guid tenantId, Employee loggedInEmployee);