diff --git a/Marco.Pms.Services/Controllers/MasterController.cs b/Marco.Pms.Services/Controllers/MasterController.cs
index 7b9baeb..7a6a48d 100644
--- a/Marco.Pms.Services/Controllers/MasterController.cs
+++ b/Marco.Pms.Services/Controllers/MasterController.cs
@@ -38,6 +38,78 @@ namespace Marco.Pms.Services.Controllers
             tenantId = userHelper.GetTenantId();
         }
 
+        #region =================================================================== Services APIs ===================================================================
+
+        [HttpGet("service/list")]
+        public async Task<IActionResult> GetServices()
+        {
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.GetServicesAsync(loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
+        }
+
+        [HttpPost("service/create")]
+        public async Task<IActionResult> CreateService([FromBody] ServiceMasterDto serviceMasterDto)
+        {
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.CreateServiceAsync(serviceMasterDto, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
+        }
+
+        [HttpPut("service/edit/{id}")]
+        public async Task<IActionResult> UpdateService(Guid id, [FromBody] ServiceMasterDto serviceMasterDto)
+        {
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.UpdateServiceAsync(id, serviceMasterDto, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
+        }
+
+        [HttpDelete("service/delete/{id}")]
+        public async Task<IActionResult> DeleteService(Guid id, [FromQuery] bool active = false)
+        {
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.DeleteServiceAsync(id, active, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
+        }
+
+        #endregion
+
+        #region =================================================================== Activity Group APIs ===================================================================
+
+        [HttpGet("activity-group/list")]
+        public async Task<IActionResult> GetActivityGroups()
+        {
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.GetActivityGroupsAsync(loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
+        }
+
+        [HttpPost("activity-group/create")]
+        public async Task<IActionResult> CreateActivityGroup([FromBody] ActivityGroupDto activityGroupDto)
+        {
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.CreateActivityGroupAsync(activityGroupDto, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
+        }
+
+        [HttpPut("activity-group/edit/{id}")]
+        public async Task<IActionResult> UpdateActivityGroup(Guid id, [FromBody] ActivityGroupDto activityGroupDto)
+        {
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.UpdateActivityGroupAsync(id, activityGroupDto, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
+
+        }
+
+        [HttpDelete("activity-group/delete/{id}")]
+        public async Task<IActionResult> DeleteActivityGroup(Guid id, [FromQuery] bool active = false)
+        {
+            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
+            var response = await _masterService.DeleteActivityGroupAsync(id, active, loggedInEmployee, tenantId);
+            return StatusCode(response.StatusCode, response);
+        }
+        #endregion
+
         #region =================================================================== Activity APIs ===================================================================
 
         [HttpGet]
diff --git a/Marco.Pms.Services/Service/MasterService.cs b/Marco.Pms.Services/Service/MasterService.cs
index 9de13fc..538cb6d 100644
--- a/Marco.Pms.Services/Service/MasterService.cs
+++ b/Marco.Pms.Services/Service/MasterService.cs
@@ -3,6 +3,7 @@ using Marco.Pms.DataAccess.Data;
 using Marco.Pms.Helpers.Utility;
 using Marco.Pms.Model.Directory;
 using Marco.Pms.Model.DocumentManager;
+using Marco.Pms.Model.Dtos.Activities;
 using Marco.Pms.Model.Dtos.DocumentManager;
 using Marco.Pms.Model.Dtos.Master;
 using Marco.Pms.Model.Employees;
@@ -11,6 +12,7 @@ using Marco.Pms.Model.Mapper;
 using Marco.Pms.Model.Master;
 using Marco.Pms.Model.MongoDBModels.Utility;
 using Marco.Pms.Model.Utilities;
+using Marco.Pms.Model.ViewModels.Activities;
 using Marco.Pms.Model.ViewModels.DocumentManager;
 using Marco.Pms.Model.ViewModels.Master;
 using Marco.Pms.Services.Helpers;
@@ -49,6 +51,645 @@ namespace Marco.Pms.Services.Service
             _cache = cache;
         }
 
+        #region =================================================================== Services APIs ===================================================================
+        public async Task<ApiResponse<object>> GetServicesAsync(Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("GetServices called");
+
+            try
+            {
+                // Step 1: Fetch services for the tenant
+                var services = await _context.ServiceMasters
+                    .Where(s => s.TenantId == tenantId && s.IsActive)
+                    .Select(s => _mapper.Map<ServiceMasterVM>(s))
+                    .ToListAsync();
+
+                _logger.LogInfo("Fetched {Count} service records for tenantId: {TenantId}", services.Count, tenantId);
+
+                return ApiResponse<object>.SuccessResponse(services, $"{services.Count} record(s) of services fetched successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error fetching services");
+                return ApiResponse<object>.ErrorResponse("An error occurred while fetching services", ex.Message, 500);
+            }
+        }
+        public async Task<ApiResponse<object>> CreateServiceAsync(ServiceMasterDto serviceMasterDto, Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("CreateService called with Name: {ServiceName}", serviceMasterDto.Name);
+
+            try
+            {
+                // Step 1: Permission check
+                var hasManagePermission = await _permission.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
+                if (!hasManagePermission)
+                {
+                    _logger.LogWarning("Access denied for employeeId: {EmployeeId}", loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse("You don't have access", "You don't have permission to take this action", 403);
+                }
+
+                // Step 2: Check for duplicate name
+                bool isExist = await _context.ServiceMasters
+                    .AnyAsync(s => s.TenantId == tenantId && s.Name == serviceMasterDto.Name);
+
+                if (isExist)
+                {
+                    _logger.LogWarning("Duplicate service name '{ServiceName}' attempted by employeeId: {EmployeeId}", serviceMasterDto.Name, loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse(
+                        $"Service with name '{serviceMasterDto.Name}' already exists",
+                        $"Service with name '{serviceMasterDto.Name}' already exists", 400);
+                }
+
+                // Step 3: Save new service
+                ServiceMaster service = _mapper.Map<ServiceMaster>(serviceMasterDto);
+                service.TenantId = tenantId;
+                service.IsActive = true;
+                service.IsSystem = false;
+                _context.ServiceMasters.Add(service);
+                await _context.SaveChangesAsync();
+
+                var response = _mapper.Map<ServiceMasterVM>(service);
+
+                _logger.LogInfo("New service '{ServiceName}' created successfully by employeeId: {EmployeeId}", service.Name, loggedInEmployee.Id);
+
+                return ApiResponse<object>.SuccessResponse(response, "New service created successfully", 201);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error creating service");
+                return ApiResponse<object>.ErrorResponse("Failed to create service", ex.Message, 500);
+            }
+        }
+        public async Task<ApiResponse<object>> UpdateServiceAsync(Guid id, ServiceMasterDto serviceMasterDto, Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("UpdateService called for Id: {Id}", id);
+
+            try
+            {
+
+                // Step 1: Permission check
+                var hasPermission = await _permission.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
+                if (!hasPermission)
+                {
+                    _logger.LogWarning("Access denied. EmployeeId: {EmployeeId} lacks Manage_Master permission.", loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse("Access denied", "You don't have permission to take this action", 403);
+                }
+
+                // Step 2: Input validation
+                if (serviceMasterDto.Id != id)
+                {
+                    _logger.LogWarning("Invalid input data provided for UpdateService. Id: {Id}", id);
+                    return ApiResponse<object>.ErrorResponse("Invalid input", "Please provide valid service data", 400);
+                }
+
+                // Step 3: Retrieve service
+                var service = await _context.ServiceMasters
+                    .FirstOrDefaultAsync(s => s.Id == id && s.TenantId == tenantId && s.IsActive);
+
+                if (service == null)
+                {
+                    _logger.LogWarning("Service not found for Id: {Id}, Tenant: {TenantId}", id, tenantId);
+                    return ApiResponse<object>.ErrorResponse("Service not found", "The requested service does not exist", 404);
+                }
+
+                // Step 4: Update and save
+                service.Name = serviceMasterDto.Name.Trim();
+                service.Description = serviceMasterDto.Description.Trim();
+
+                await _context.SaveChangesAsync();
+
+                var response = _mapper.Map<ServiceMasterVM>(service);
+
+                _logger.LogInfo("Service updated successfully. Id: {Id}, TenantId: {TenantId}", service.Id, tenantId);
+                return ApiResponse<object>.SuccessResponse(response, "Service updated successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error while updating service Id: {Id}.", id);
+                return ApiResponse<object>.ErrorResponse("An error occurred while updating the service", ex.Message, 500);
+            }
+        }
+        public async Task<ApiResponse<object>> DeleteServiceAsync(Guid id, bool active, Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("DeleteService called with ServiceId: {ServiceId}, IsActive: {IsActive}", id, active);
+
+            try
+            {
+                // Step 1: Get validate permission
+                var hasPermission = await _permission.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
+
+                if (!hasPermission)
+                {
+                    _logger.LogWarning("Access denied. EmployeeId: {EmployeeId} does not have Manage_Master permission.", loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse("Access denied", "You don't have permission to delete services", 403);
+                }
+
+                // Step 2: Check if the service exists
+                var service = await _context.ServiceMasters
+                    .FirstOrDefaultAsync(s => s.Id == id && s.TenantId == tenantId);
+
+                if (service == null)
+                {
+                    _logger.LogWarning("Service not found. ServiceId: {ServiceId}", id);
+                    return ApiResponse<object>.ErrorResponse("Service not found", "Service not found or already deleted", 404);
+                }
+
+                // Protect system-defined service
+                if (service.IsSystem)
+                {
+                    _logger.LogWarning("Attempt to delete system-defined service. ServiceId: {ServiceId}", id);
+                    return ApiResponse<object>.ErrorResponse("Cannot delete system-defined service", "This service is system-defined and cannot be deleted", 400);
+                }
+
+                // Step 3: Soft delete or restore
+                service.IsActive = active;
+                await _context.SaveChangesAsync();
+
+                var status = active ? "restored" : "deactivated";
+                _logger.LogInfo("Service {ServiceId} has been {Status} successfully by EmployeeId: {EmployeeId}", id, status, loggedInEmployee.Id);
+
+                return ApiResponse<object>.SuccessResponse(new { }, $"Service {status} successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Unexpected error occurred while deleting service {ServiceId}", id);
+                return ApiResponse<object>.ErrorResponse("Error deleting service", ex.Message, 500);
+            }
+        }
+        #endregion
+
+        #region =================================================================== Activity Group APIs ===================================================================
+
+        public async Task<ApiResponse<object>> GetActivityGroupsAsync(Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("GetActivityGroups called");
+
+            try
+            {
+                // Step 1: Fetch all activity groups for the tenant
+                var activityGroups = await _context.ActivityGroupMasters
+                    .Include(ag => ag.Service)
+                    .Where(ag => ag.TenantId == tenantId && ag.IsActive)
+                    .Select(ag => _mapper.Map<ActivityGroupMasterVM>(ag))
+                    .ToListAsync();
+
+                _logger.LogInfo("{Count} activity group(s) fetched for tenantId: {TenantId}", activityGroups.Count, tenantId);
+
+                return ApiResponse<object>.SuccessResponse(activityGroups, $"{activityGroups.Count} record(s) of activity groups fetched successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error fetching activity groups");
+                return ApiResponse<object>.ErrorResponse("An error occurred while fetching activity groups", ex.Message, 500);
+            }
+        }
+        public async Task<ApiResponse<object>> CreateActivityGroupAsync(ActivityGroupDto activityGroupDto, Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("CreateActivityGroup called with Name: {Name}", activityGroupDto.Name);
+
+            try
+            {
+                // Step 1: Check Manage Master permission
+                var hasPermission = await _permission.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
+                if (!hasPermission)
+                {
+                    _logger.LogWarning("Access denied. EmployeeId: {EmployeeId} lacks Manage_Master permission", loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse("Access denied", "You don't have permission to take this action", 403);
+                }
+
+                // Step 2: Check for duplicate name within ActivityGroupMasters
+                bool isExist = await _context.ActivityGroupMasters
+                    .AnyAsync(ag => ag.TenantId == tenantId && ag.Name.ToLower() == activityGroupDto.Name.ToLower());
+
+                if (isExist)
+                {
+                    _logger.LogWarning("Duplicate activity group name '{Name}' attempted by employeeId: {EmployeeId}", activityGroupDto.Name, loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse(
+                        $"Activity group with name '{activityGroupDto.Name}' already exists",
+                        $"Activity group with name '{activityGroupDto.Name}' already exists", 400);
+                }
+
+                // Step 3: Map and persist
+                var activityGroup = _mapper.Map<ActivityGroupMaster>(activityGroupDto);
+                activityGroup.TenantId = tenantId;
+                activityGroup.IsActive = true;
+                activityGroup.IsSystem = false;
+
+                _context.ActivityGroupMasters.Add(activityGroup);
+                await _context.SaveChangesAsync();
+
+                var service = await _context.ServiceMasters.FirstOrDefaultAsync(s => s.Id == activityGroup.ServiceId);
+
+                var response = _mapper.Map<ActivityGroupMasterVM>(activityGroup);
+
+                _logger.LogInfo("New activity group '{Name}' created successfully by employeeId: {EmployeeId}", activityGroup.Name, loggedInEmployee.Id);
+                return ApiResponse<object>.SuccessResponse(response, "New activity group created successfully", 201);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error creating activity group");
+                return ApiResponse<object>.ErrorResponse("Failed to create activity group", ex.Message, 500);
+            }
+        }
+        public async Task<ApiResponse<object>> UpdateActivityGroupAsync(Guid id, ActivityGroupDto activityGroupDto, Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("UpdateActivityGroup called for Id: {Id}", id);
+
+            try
+            {
+                // Step 1: Permission check
+                var hasPermission = await _permission.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
+                if (!hasPermission)
+                {
+                    _logger.LogWarning("Access denied. EmployeeId: {EmployeeId} lacks Manage_Master permission.", loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse("Access denied", "You don't have permission to take this action", 403);
+                }
+
+                // Step 2: Input validation
+                if (activityGroupDto.Id != id)
+                {
+                    _logger.LogWarning("Invalid input for activity group update. Id: {Id}", id);
+                    return ApiResponse<object>.ErrorResponse("Invalid input", "Please provide valid data to update activity group", 400);
+                }
+
+                var service = await _context.ServiceMasters.FirstOrDefaultAsync(s => s.Id == activityGroupDto.ServiceId && s.IsActive);
+
+                if (service == null)
+                {
+                    _logger.LogWarning("User tries to update activity group, but service not found");
+                    return ApiResponse<object>.ErrorResponse("Invalid service ID", "Please provide valid service ID to update activity group", 400);
+                }
+
+                // Step 3: Retrieve existing activity group
+                var activityGroup = await _context.ActivityGroupMasters
+                    .Include(ag => ag.Service)
+                    .FirstOrDefaultAsync(ag => ag.Id == id && ag.TenantId == tenantId && ag.IsActive);
+
+                if (activityGroup == null)
+                {
+                    _logger.LogWarning("Activity group not found. Id: {Id}, TenantId: {TenantId}", id, tenantId);
+                    return ApiResponse<object>.ErrorResponse("Activity group not found", "No such activity group exists", 404);
+                }
+
+                // Step 4: Update and save
+                activityGroup.Name = activityGroupDto.Name.Trim();
+                activityGroup.Description = activityGroupDto.Description.Trim();
+
+                await _context.SaveChangesAsync();
+
+                var response = _mapper.Map<ActivityGroupMasterVM>(activityGroup);
+
+                _logger.LogInfo("Activity group updated successfully. Id: {Id}, TenantId: {TenantId}", activityGroup.Id, tenantId);
+                return ApiResponse<object>.SuccessResponse(response, "Activity group updated successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error while updating activity group Id: {Id}", id);
+                return ApiResponse<object>.ErrorResponse("An error occurred while updating the activity group", ex.Message, 500);
+            }
+        }
+        public async Task<ApiResponse<object>> DeleteActivityGroupAsync(Guid id, bool isActive, Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("DeleteActivityGroup called with ActivityGroupId: {ActivityGroupId}, IsActive: {IsActive}", id, isActive);
+
+            try
+            {
+                // Step 1: Permission check
+                var hasPermission = await _permission.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
+
+                if (!hasPermission)
+                {
+                    _logger.LogWarning("Access denied. EmployeeId: {EmployeeId} does not have Manage_Master permission.", loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse("Access denied", "You don't have permission to delete activity groups", 403);
+                }
+
+                // Step 2: Fetch the activity group
+                var activityGroup = await _context.ActivityGroupMasters
+                    .FirstOrDefaultAsync(ag => ag.Id == id && ag.TenantId == tenantId);
+
+                if (activityGroup == null)
+                {
+                    _logger.LogWarning("ActivityGroup not found. Id: {ActivityGroupId}", id);
+                    return ApiResponse<object>.ErrorResponse("Activity group not found", "Activity group not found or already deleted", 404);
+                }
+
+                //Protect system-defined activity group
+                if (activityGroup.IsSystem)
+                {
+                    _logger.LogWarning("Attempt to delete system-defined activity group. Id: {ActivityGroupId}", id);
+                    return ApiResponse<object>.ErrorResponse("Cannot delete system-defined activity group", "This activity group is system-defined and cannot be deleted", 400);
+                }
+
+                // Step 3: Perform soft delete or restore
+                activityGroup.IsActive = isActive;
+                await _context.SaveChangesAsync();
+
+                var status = isActive ? "restored" : "deactivated";
+                _logger.LogInfo("ActivityGroup {ActivityGroupId} has been {Status} by EmployeeId: {EmployeeId}", id, status, loggedInEmployee.Id);
+
+                return ApiResponse<object>.SuccessResponse(new { }, $"Activity group {status} successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Unexpected error occurred while deleting ActivityGroup {ActivityGroupId}", id);
+                return ApiResponse<object>.ErrorResponse("Error deleting activity group", ex.Message, 500);
+            }
+        }
+
+        #endregion
+
+        #region =================================================================== Activity APIs ===================================================================
+        public async Task<ApiResponse<object>> GetActivitiesMasterAsync(Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("GetActivitiesMaster called");
+
+            try
+            {
+                // Step 1: Fetch all active activities for the tenant
+                var activities = await _context.ActivityMasters
+                    .Include(c => c.ActivityGroup)
+                        .ThenInclude(ag => ag!.Service)
+                    .Where(c => c.TenantId == tenantId && c.IsActive)
+                    .ToListAsync();
+
+                if (activities.Count == 0)
+                {
+                    _logger.LogWarning("No active activities found for tenantId: {TenantId}", tenantId);
+                    return ApiResponse<object>.SuccessResponse(new List<ActivityVM>(), "No activity records found", 200);
+                }
+
+                // Step 2: Fetch all checklists for those activities in a single query to avoid N+1
+                var activityIds = activities.Select(a => a.Id).ToList();
+                var checkLists = await _context.ActivityCheckLists
+                    .Where(c => c.TenantId == tenantId && activityIds.Contains(c.ActivityId))
+                    .ToListAsync();
+
+                // Step 3: Group checklists by activity
+                var groupedChecklists = checkLists
+                    .GroupBy(c => c.ActivityId)
+                    .ToDictionary(g => g.Key, g => g.ToList());
+
+                // Step 4: Map to ViewModel
+                var activityVMs = activities.Select(activity =>
+                {
+                    var checklistForActivity = groupedChecklists.ContainsKey(activity.Id)
+                        ? groupedChecklists[activity.Id]
+                        : new List<ActivityCheckList>();
+
+                    var response = _mapper.Map<ActivityVM>(activity);
+                    response.CheckLists = _mapper.Map<List<CheckListVM>>(checklistForActivity);
+                    return response;
+
+                }).ToList();
+
+                _logger.LogInfo("{Count} activity records fetched successfully for tenantId: {TenantId}", activityVMs.Count, tenantId);
+
+                return ApiResponse<object>.SuccessResponse(activityVMs, $"{activityVMs.Count} activity records fetched successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error occurred in GetActivitiesMaster");
+                return ApiResponse<object>.ErrorResponse("Failed to fetch activity records", ex.Message, 500);
+            }
+        }
+        public async Task<ApiResponse<object>> CreateActivityAsync(CreateActivityMasterDto createActivity, Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("CreateActivity called with ActivityName: {Name}", createActivity?.ActivityName ?? "null");
+
+            try
+            {
+                // Step 1: Validate input
+                if (createActivity == null)
+                {
+                    _logger.LogWarning("Null request body received in CreateActivity");
+                    return ApiResponse<object>.ErrorResponse("Invalid input", "Activity data is required", 400);
+                }
+
+                var activityGroup = await _context.ActivityGroupMasters
+                    .Include(ag => ag.Service)
+                    .FirstOrDefaultAsync(ag => ag.Id == createActivity.ActitvityGroupId && ag.TenantId == tenantId);
+                if (activityGroup == null)
+                {
+                    _logger.LogWarning("User tried to create new activity, but not found activity group");
+                    return ApiResponse<object>.ErrorResponse("Invalid input", "Activity data is required", 400);
+                }
+
+                // Step 2: Check permissions
+                var hasPermission = await _permission.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
+                if (!hasPermission)
+                {
+                    _logger.LogWarning("Access denied. EmployeeId: {EmployeeId} does not have Manage_Master permission.", loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse("Access denied", "You don't have permission to perform this action", 403);
+                }
+
+                // Step 3: Convert DTO to entity and add activity
+                var activityMaster = _mapper.Map<ActivityMaster>(createActivity);
+                activityMaster.TenantId = tenantId;
+
+                _context.ActivityMasters.Add(activityMaster);
+                await _context.SaveChangesAsync();
+
+                List<CheckListVM> checkListVMs = new();
+
+                // Step 4: Handle checklist items if present
+                if (createActivity.CheckList?.Any() == true)
+                {
+                    var activityCheckLists = createActivity.CheckList
+                        .Select(c =>
+                        {
+                            var response = _mapper.Map<ActivityCheckList>(c);
+                            response.ActivityId = activityMaster.Id;
+                            response.IsChecked = false;
+                            response.TenantId = tenantId;
+                            return response;
+                        })
+                        .ToList();
+
+                    _context.ActivityCheckLists.AddRange(activityCheckLists);
+                    await _context.SaveChangesAsync();
+
+                    checkListVMs = activityCheckLists
+                        .Select(c =>
+                        {
+                            var response = _mapper.Map<CheckListVM>(c);
+                            return response;
+                        })
+                        .ToList();
+                }
+
+                // Step 5: Prepare final response
+                var activityVM = _mapper.Map<ActivityVM>(activityMaster);
+                activityVM.CheckLists = checkListVMs;
+
+                _logger.LogInfo("Activity '{Name}' created successfully for tenant {TenantId}", activityMaster.ActivityName, tenantId);
+                return ApiResponse<object>.SuccessResponse(activityVM, "Activity created successfully", 201);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error occurred while creating activity");
+                return ApiResponse<object>.ErrorResponse("An error occurred while creating activity", ex.Message, 500);
+            }
+        }
+        public async Task<ApiResponse<object>> UpdateActivityAsync(Guid id, CreateActivityMasterDto createActivity, Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("UpdateActivity called for ActivityId: {ActivityId}", id);
+
+            try
+            {
+                // Step 1: Validate input
+                if (createActivity == null || string.IsNullOrWhiteSpace(createActivity.ActivityName) || string.IsNullOrWhiteSpace(createActivity.UnitOfMeasurement))
+                {
+                    _logger.LogWarning("Invalid activity update input for ActivityId: {ActivityId}", id);
+                    return ApiResponse<object>.ErrorResponse("Invalid input", "ActivityName and UnitOfMeasurement are required", 400);
+                }
+
+                // Step 2: Check permissions
+                var hasPermission = await _permission.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
+                if (!hasPermission)
+                {
+                    _logger.LogWarning("Access denied for employeeId: {EmployeeId}", loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse("Access denied", "You don't have permission to update activities", 403);
+                }
+
+                // Step 3: Validate service, activity group, and activity existence
+                var activityGroup = await _context.ActivityGroupMasters.Include(ag => ag.Service).FirstOrDefaultAsync(ag => ag.Id == createActivity.ActitvityGroupId && ag.IsActive);
+
+                if (activityGroup == null)
+                {
+                    _logger.LogWarning("User tries to update activity, but cannot able found activity group or service");
+                    return ApiResponse<object>.ErrorResponse("Invalid activity group ID or service ID", "Please provide valid activity group ID or service ID to update activity group", 400);
+                }
+
+                var activity = await _context.ActivityMasters
+                    .Include(a => a.ActivityGroup)
+                        .ThenInclude(ag => ag!.Service)
+                    .FirstOrDefaultAsync(a => a.Id == id && a.IsActive && a.TenantId == tenantId);
+
+                if (activity == null)
+                {
+                    _logger.LogWarning("Activity not found for ActivityId: {ActivityId}, TenantId: {TenantId}", id, tenantId);
+                    return ApiResponse<object>.ErrorResponse("Activity not found", "Activity not found", 404);
+                }
+
+                // Step 4: Update activity core data
+                activity.ActivityName = createActivity.ActivityName.Trim();
+                activity.UnitOfMeasurement = createActivity.UnitOfMeasurement.Trim();
+                activity.ActivityGroupId = createActivity.ActitvityGroupId;
+
+                await _context.SaveChangesAsync();
+
+                // Step 5: Handle checklist updates
+                var existingChecklists = await _context.ActivityCheckLists
+                    .AsNoTracking()
+                    .Where(c => c.ActivityId == activity.Id)
+                    .ToListAsync();
+
+                var updatedChecklistVMs = new List<CheckListVM>();
+
+                if (createActivity.CheckList != null && createActivity.CheckList.Any())
+                {
+                    var incomingCheckIds = createActivity.CheckList.Where(c => c.Id != null).Select(c => c.Id!.Value).ToHashSet();
+
+                    // Prepare lists
+                    var newChecks = createActivity.CheckList.Where(c => c.Id == null);
+                    var updates = createActivity.CheckList.Where(c => c.Id != null && existingChecklists.Any(ec => ec.Id == c.Id));
+                    var deletes = existingChecklists.Where(ec => !incomingCheckIds.Contains(ec.Id)).ToList();
+
+                    var toAdd = newChecks
+                        .Select(c =>
+                        {
+                            var response = _mapper.Map<ActivityCheckList>(c);
+                            response.ActivityId = activity.Id;
+                            response.IsChecked = false;
+                            response.TenantId = tenantId;
+                            return response;
+                        })
+                        .ToList();
+
+                    var toUpdate = updates
+                        .Select(c =>
+                        {
+                            var response = _mapper.Map<ActivityCheckList>(c);
+                            response.ActivityId = activity.Id;
+                            response.TenantId = tenantId;
+                            return response;
+                        })
+                        .ToList();
+
+                    _context.ActivityCheckLists.AddRange(toAdd);
+                    _context.ActivityCheckLists.UpdateRange(toUpdate);
+                    _context.ActivityCheckLists.RemoveRange(deletes);
+
+                    await _context.SaveChangesAsync();
+
+                    // Prepare view model
+                    updatedChecklistVMs = toAdd.Concat(toUpdate)
+                        .Select(c => _mapper.Map<CheckListVM>(c))
+                        .ToList();
+                }
+                else if (existingChecklists.Any())
+                {
+                    // If no checklist provided, remove all existing
+                    _context.ActivityCheckLists.RemoveRange(existingChecklists);
+                    await _context.SaveChangesAsync();
+                }
+
+                // Step 6: Prepare response
+                var activityVM = _mapper.Map<ActivityVM>(activity);
+                activityVM.CheckLists = updatedChecklistVMs;
+
+                _logger.LogInfo("Activity updated successfully. ActivityId: {ActivityId}, TenantId: {TenantId}", activity.Id, tenantId);
+                return ApiResponse<object>.SuccessResponse(activityVM, "Activity updated successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Exception in UpdateActivity");
+                return ApiResponse<object>.ErrorResponse("Error updating activity", ex.Message, 500);
+            }
+        }
+        public async Task<ApiResponse<object>> DeleteActivityAsync(Guid id, bool isActive, Employee loggedInEmployee, Guid tenantId)
+        {
+            _logger.LogInfo("DeleteActivity called with ActivityId: {ActivityId}, IsActive: {IsActive}", id, isActive);
+
+            try
+            {
+                // Step 1: Validate permission
+                var hasPermission = await _permission.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
+
+                if (!hasPermission)
+                {
+                    _logger.LogWarning("Access denied for EmployeeId: {EmployeeId}", loggedInEmployee.Id);
+                    return ApiResponse<object>.ErrorResponse("Access denied", "You don't have permission to delete activities", 403);
+                }
+
+                // Step 2: Fetch the activity
+                var activity = await _context.ActivityMasters
+                    .FirstOrDefaultAsync(a => a.Id == id && a.TenantId == tenantId);
+
+                if (activity == null)
+                {
+                    _logger.LogWarning("Activity not found. ActivityId: {ActivityId}", id);
+                    return ApiResponse<object>.ErrorResponse("Activity not found", "Activity not found or already deleted", 404);
+                }
+
+                // Step 3: Perform soft delete/restore
+                activity.IsActive = isActive;
+                await _context.SaveChangesAsync();
+
+                string status = isActive ? "restored" : "deactivated";
+                _logger.LogInfo("Activity {ActivityId} {Status} successfully by EmployeeId: {EmployeeId}", id, status, loggedInEmployee.Id);
+
+                return ApiResponse<object>.SuccessResponse(new { }, $"Activity {status} successfully", 200);
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Unexpected error while deleting activity {ActivityId}", id);
+                return ApiResponse<object>.ErrorResponse("Error deleting activity", ex.Message, 500);
+            }
+        }
+
+        #endregion
+
         #region =================================================================== Contact Category APIs ===================================================================
 
         public async Task<ApiResponse<object>> CreateContactCategory(CreateContactCategoryDto contactCategoryDto, Employee loggedInEmployee, Guid tenantId)
diff --git a/Marco.Pms.Services/Service/ServiceInterfaces/IMasterService.cs b/Marco.Pms.Services/Service/ServiceInterfaces/IMasterService.cs
index 6ef4310..bc3db69 100644
--- a/Marco.Pms.Services/Service/ServiceInterfaces/IMasterService.cs
+++ b/Marco.Pms.Services/Service/ServiceInterfaces/IMasterService.cs
@@ -7,6 +7,20 @@ namespace Marco.Pms.Services.Service.ServiceInterfaces
 {
     public interface IMasterService
     {
+        #region =================================================================== Service Master APIs ===================================================================
+        Task<ApiResponse<object>> GetServicesAsync(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 Group Master APIs ===================================================================
+        Task<ApiResponse<object>> GetActivityGroupsAsync(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);
+
+        #endregion
         #region =================================================================== Contact Category APIs ===================================================================
         Task<ApiResponse<object>> CreateContactCategory(CreateContactCategoryDto contactCategoryDto, Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> UpdateContactCategory(Guid id, UpdateContactCategoryDto contactCategoryDto, Employee loggedInEmployee, Guid tenantId);
@@ -14,6 +28,7 @@ namespace Marco.Pms.Services.Service.ServiceInterfaces
         Task<ApiResponse<object>> GetContactCategoryById(Guid id, Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> DeleteContactCategory(Guid id, Employee loggedInEmployee, Guid tenantId);
         #endregion
+
         #region =================================================================== Contact Tag APIs ===================================================================
         Task<ApiResponse<Object>> GetContactTags(Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> CreateContactTag(CreateContactTagDto contactTagDto, Employee loggedInEmployee, Guid tenantId);
@@ -21,6 +36,7 @@ namespace Marco.Pms.Services.Service.ServiceInterfaces
         Task<ApiResponse<object>> DeleteContactTag(Guid id, Employee loggedInEmployee, Guid tenantId);
 
         #endregion
+
         #region =================================================================== Work Status APIs ===================================================================
         Task<ApiResponse<object>> GetWorkStatusList(Employee loggedInEmployee, Guid tenantId);
         Task<ApiResponse<object>> CreateWorkStatus(CreateWorkStatusMasterDto createWorkStatusDto, Employee loggedInEmployee, Guid tenantId);