diff --git a/src/Umbraco.Web.BackOffice/Controllers/RelationController.cs b/src/Umbraco.Web.BackOffice/Controllers/RelationController.cs
new file mode 100644
index 0000000000..699c06f1d9
--- /dev/null
+++ b/src/Umbraco.Web.BackOffice/Controllers/RelationController.cs
@@ -0,0 +1,75 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Net.Http;
+using Microsoft.AspNetCore.Mvc;
+using Umbraco.Core;
+using Umbraco.Core.Mapping;
+using Umbraco.Core.Models;
+using Umbraco.Core.Services;
+using Umbraco.Web.BackOffice.Filters;
+using Umbraco.Web.Common.ActionsResults;
+using Umbraco.Web.Common.Attributes;
+using Umbraco.Web.Editors;
+using Umbraco.Web.Models.ContentEditing;
+using Constants = Umbraco.Core.Constants;
+
+namespace Umbraco.Web.BackOffice.Controllers
+{
+    [PluginController("UmbracoApi")]
+    [TypeFilter(typeof(UmbracoApplicationAuthorizeAttribute), Arguments = new object[]{new string[]{Constants.Applications.Content} })]
+    public class RelationController : UmbracoAuthorizedJsonController
+    {
+        private readonly UmbracoMapper _umbracoMapper;
+        private readonly IRelationService _relationService;
+
+        public RelationController(UmbracoMapper umbracoMapper,
+            IRelationService relationService)
+        {
+            _umbracoMapper = umbracoMapper ?? throw new ArgumentNullException(nameof(umbracoMapper));
+            _relationService = relationService ?? throw new ArgumentNullException(nameof(relationService));
+        }
+
+        public RelationDisplay GetById(int id)
+        {
+            return _umbracoMapper.Map<IRelation, RelationDisplay>(_relationService.GetById(id));
+        }
+
+        //[EnsureUserPermissionForContent("childId")]
+        public IEnumerable<RelationDisplay> GetByChildId(int childId, string relationTypeAlias = "")
+        {
+            var relations = _relationService.GetByChildId(childId).ToArray();
+
+            if (relations.Any() == false)
+            {
+                return Enumerable.Empty<RelationDisplay>();
+            }
+
+            if (string.IsNullOrWhiteSpace(relationTypeAlias) == false)
+            {
+                return
+                    _umbracoMapper.MapEnumerable<IRelation, RelationDisplay>(
+                        relations.Where(x => x.RelationType.Alias.InvariantEquals(relationTypeAlias)));
+            }
+
+            return _umbracoMapper.MapEnumerable<IRelation, RelationDisplay>(relations);
+        }
+
+        [HttpDelete]
+        [HttpPost]
+        public IActionResult DeleteById(int id)
+        {
+            var foundRelation = _relationService.GetById(id);
+
+            if (foundRelation == null)
+            {
+                return new UmbracoProblemResult("No relation found with the specified id", HttpStatusCode.NotFound);
+            }
+
+            _relationService.Delete(foundRelation);
+
+            return Ok();
+        }
+    }
+}
diff --git a/src/Umbraco.Web/Editors/BackOfficeServerVariables.cs b/src/Umbraco.Web/Editors/BackOfficeServerVariables.cs
index 46995fd7ba..689fa39553 100644
--- a/src/Umbraco.Web/Editors/BackOfficeServerVariables.cs
+++ b/src/Umbraco.Web/Editors/BackOfficeServerVariables.cs
@@ -233,10 +233,10 @@ namespace Umbraco.Web.Editors
                         //     "packageApiBaseUrl", _urlHelper.GetUmbracoApiServiceBaseUrl<PackageController>(
                         //         controller => controller.GetCreatedPackages())
                         // },
-                        {
-                            "relationApiBaseUrl", _urlHelper.GetUmbracoApiServiceBaseUrl<RelationController>(
-                                controller => controller.GetById(0))
-                        },
+                        // {
+                        //     "relationApiBaseUrl", _urlHelper.GetUmbracoApiServiceBaseUrl<RelationController>(
+                        //         controller => controller.GetById(0))
+                        // },
                         // {
                         //     "rteApiBaseUrl", _urlHelper.GetUmbracoApiServiceBaseUrl<RichTextPreValueController>(
                         //         controller => controller.GetConfiguration())
diff --git a/src/Umbraco.Web/Editors/RelationController.cs b/src/Umbraco.Web/Editors/RelationController.cs
deleted file mode 100644
index b7f9baba55..0000000000
--- a/src/Umbraco.Web/Editors/RelationController.cs
+++ /dev/null
@@ -1,60 +0,0 @@
-using System.Collections.Generic;
-using System.Linq;
-using System.Net;
-using System.Net.Http;
-using System.Web.Http;
-using Umbraco.Core;
-using Umbraco.Core.Models;
-using Umbraco.Web.Models.ContentEditing;
-using Umbraco.Web.Mvc;
-using Umbraco.Web.WebApi.Filters;
-using Constants = Umbraco.Core.Constants;
-
-namespace Umbraco.Web.Editors
-{
-    [PluginController("UmbracoApi")]
-    [UmbracoApplicationAuthorize(Constants.Applications.Content)]
-    public class RelationController : UmbracoAuthorizedJsonController
-    {
-        public RelationDisplay GetById(int id)
-        {
-            return Mapper.Map<IRelation, RelationDisplay>(Services.RelationService.GetById(id));
-        }
-
-        //[EnsureUserPermissionForContent("childId")]
-        public IEnumerable<RelationDisplay> GetByChildId(int childId, string relationTypeAlias = "")
-        {
-            var relations = Services.RelationService.GetByChildId(childId).ToArray();
-
-            if (relations.Any() == false)
-            {
-                return Enumerable.Empty<RelationDisplay>();
-            }
-
-            if (string.IsNullOrWhiteSpace(relationTypeAlias) == false)
-            {
-                return
-                    Mapper.MapEnumerable<IRelation, RelationDisplay>(
-                        relations.Where(x => x.RelationType.Alias.InvariantEquals(relationTypeAlias)));
-            }
-
-            return Mapper.MapEnumerable<IRelation, RelationDisplay>(relations);
-        }
-
-        [HttpDelete]
-        [HttpPost]
-        public HttpResponseMessage DeleteById(int id)
-        {
-            var foundRelation = Services.RelationService.GetById(id);
-
-            if (foundRelation == null)
-            {
-                return Request.CreateErrorResponse(HttpStatusCode.NotFound, "No relation found with the specified id");
-            }
-
-            Services.RelationService.Delete(foundRelation);
-
-            return Request.CreateResponse(HttpStatusCode.OK);
-        }
-    }
-}
diff --git a/src/Umbraco.Web/Umbraco.Web.csproj b/src/Umbraco.Web/Umbraco.Web.csproj
index 87c653e71f..a5ed5fdde3 100755
--- a/src/Umbraco.Web/Umbraco.Web.csproj
+++ b/src/Umbraco.Web/Umbraco.Web.csproj
@@ -331,7 +331,6 @@
     <Compile Include="Controllers\UmbLoginStatusController.cs" />
     <Compile Include="Editors\Filters\ContentSaveValidationAttribute.cs" />
     <Compile Include="Editors\ContentTypeControllerBase.cs" />
-    <Compile Include="Editors\RelationController.cs" />
     <Compile Include="GridTemplateExtensions.cs" />
     <Compile Include="Editors\TemplateQueryController.cs" />
     <Compile Include="Mvc\ActionExecutedEventArgs.cs" />