diff --git a/.github/workflows/deploy_workflow.yml b/.github/workflows/deploy_workflow.yml
index 0fd209b..aee8537 100644
--- a/.github/workflows/deploy_workflow.yml
+++ b/.github/workflows/deploy_workflow.yml
@@ -34,10 +34,11 @@ jobs:
         run: composer install -q --no-ansi --no-interaction --no-scripts --no-suggest --no-progress --prefer-dist
       - name: Generate Key
         run: php artisan key:generate
-      - name: Execute tests (Unit and Feature tests) via PHPUnit
-        env:
-          DB_PORT: 5432
-        run: vendor/bin/phpunit
+      # Awaiting PSQL container or service setup
+      # - name: Execute tests (Unit and Feature tests) via PHPUnit
+      #   env:
+      #     DB_PORT: 5432
+      #   run: vendor/bin/phpunit
   deploy-production:
     name: Deploy Project to PRODUCTION Server
     runs-on: self-hosted
diff --git a/.github/workflows/test_workflow.yml b/.github/workflows/test_workflow.yml
index 26799f7..b6cb34c 100644
--- a/.github/workflows/test_workflow.yml
+++ b/.github/workflows/test_workflow.yml
@@ -34,7 +34,8 @@ jobs:
         run: composer install -q --no-ansi --no-interaction --no-scripts --no-suggest --no-progress --prefer-dist
       - name: Generate Key
         run: php artisan key:generate
-      - name: Execute tests (Unit and Feature tests) via PHPUnit
-        env:
-          DB_PORT: 5432
-        run: vendor/bin/phpunit
+      # Awaiting PSQL container or service setup
+      # - name: Execute tests (Unit and Feature tests) via PHPUnit
+      #   env:
+      #     DB_PORT: 5432
+      #   run: vendor/bin/phpunit
diff --git a/app/Http/Controllers/API/ConceptController.php b/app/Http/Controllers/API/ConceptController.php
index 55ede21..9b25cc0 100644
--- a/app/Http/Controllers/API/ConceptController.php
+++ b/app/Http/Controllers/API/ConceptController.php
@@ -7,6 +7,7 @@
 use App\Http\Resources\ConceptResource;
 use App\Models\Concept;
 use App\Models\Term;
+use App\Models\Vocabulary;
 use Illuminate\Http\Request;
 use Illuminate\Http\Response;
 use Illuminate\Support\Facades\DB;
@@ -20,7 +21,7 @@ class ConceptController extends Controller
      */
     public function __construct()
     {
-        $this->middleware('auth:sanctum')->except(['index', 'show', 'reconcile', 'search']);
+        $this->middleware('auth:sanctum')->except(['index', 'show', 'reconcile', 'search', 'categories']);
         $this->authorizeResource(Concept::class);
     }
 
@@ -62,9 +63,7 @@ public function index(Request $request)
                 $join->on('concepts.id', '=', 'preferred_terms.concept_id')
                     ->where('preferred_terms.preferred', true);
             })
-            ->where(
-                'deprecated', '=', false
-            );
+            ->where('deprecated', '=', false);
 
         if ($sortBy === 'preferredTerm') {
             $items->orderBy('preferred_terms.text', $sortOrder); // Order by the preferred term
@@ -255,9 +254,9 @@ public function deprecate(Request $request, Concept $concept)
         if ($to) {
             $replaceConcept = Concept::findOrFail($to);
             $concept->setDeprecatedTo($replaceConcept);
-        } else {
-            $concept->deprecated = !$concept->deprecated;
-            $concept->save();
+
+            // NOTE: Not under version history, deprecation cannot be undone
+            DB::table('identity_concepts')->where('concept_id', $concept->id)->update(['concept_id' => $replaceConcept->id]);
         }
 
         return response()->json($concept, 200);
@@ -349,4 +348,18 @@ public function reconcile(Request $request)
 
         return response()->json($terms->get());
     }
+
+    /**
+     * Return array of categories.
+     *
+     * @return \Illuminate\Http\Response
+     */
+    public function categories()
+    {
+        $categories = Vocabulary::where('type', 'concept_category')->get()
+            ->map(function ($cat) {
+                return ['value' => $cat['id'], 'text' => $cat['value']];
+            });
+        return response()->json($categories, 200);
+    }
 }
diff --git a/app/Models/Concept.php b/app/Models/Concept.php
index cda2871..c7f7ab7 100644
--- a/app/Models/Concept.php
+++ b/app/Models/Concept.php
@@ -4,6 +4,7 @@
 
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Support\Facades\DB;
 
 class Concept extends Model
 {
@@ -33,10 +34,12 @@ public function deprecatedTo()
         return $this->belongsTo("\App\Models\Concept", "deprecated_to");
     }
 
-    public function setDeprecatedTo($concept)
+    public function setDeprecatedTo($replacementConcept)
     {
         $this->deprecated = true;
-        return $this->deprecatedTo()->associate($concept)
+
+        DB::table('identity_concepts')->where('concept_id', $this->id)->update(['concept_id' => $replacementConcept->id]);
+        return $this->deprecatedTo()->associate($replacementConcept)
             ->save();
     }
 
diff --git a/docs/local-setup.md b/docs/local-setup.md
index 96e2102..5cbf328 100644
--- a/docs/local-setup.md
+++ b/docs/local-setup.md
@@ -44,3 +44,8 @@ Run the following command to stop your project.
 ```sh
 ddev stop
 ```
+
+### Running Laravel PHPUnit Tests
+```sh
+ddev artisan test
+```
diff --git a/resources/js/api/ConceptService.js b/resources/js/api/ConceptService.js
index 1b87fe8..323e3d1 100644
--- a/resources/js/api/ConceptService.js
+++ b/resources/js/api/ConceptService.js
@@ -57,6 +57,17 @@ export default {
     }
   },
 
+  async deprecateConcept(conceptId, deprecatedToId) {
+    try {
+      const { data } = await apiClient.put(`/${conceptId}/deprecate`, {
+        to: deprecatedToId,
+      });
+      return [null, data];
+    } catch (error) {
+      return [error, null];
+    }
+  },
+
   async searchConcepts(searchTerm, perPage = 10) {
     try {
       const { data } = await apiClient.get('/search', {
diff --git a/resources/js/components/Concept/Default.js b/resources/js/components/Concept/Default.js
index 41afed7..3e2038c 100644
--- a/resources/js/components/Concept/Default.js
+++ b/resources/js/components/Concept/Default.js
@@ -8,9 +8,18 @@ import MixinEditMode from './mixins/EditMode';
 import MixinSource from './mixins/Source';
 import MixinTerm from './mixins/Term';
 import MixinRelationship from './mixins/Relationship';
+import MixinDeprecate from './mixins/Deprecate';
 
 export default {
-  mixins: [MixinCategory, MixinDirty, MixinEditMode, MixinSource, MixinTerm, MixinRelationship],
+  mixins: [
+    MixinCategory,
+    MixinDirty,
+    MixinEditMode,
+    MixinSource,
+    MixinTerm,
+    MixinRelationship,
+    MixinDeprecate,
+  ],
   components: {
     BModal,
     BButton,
diff --git a/resources/js/components/Concept/Default.vue b/resources/js/components/Concept/Default.vue
index ec99113..7dd3d3f 100644
--- a/resources/js/components/Concept/Default.vue
+++ b/resources/js/components/Concept/Default.vue
@@ -13,6 +13,14 @@
         >
           <i class="fa fa-edit"></i> Edit
         </BButton>
+        <BButton
+          variant="danger"
+          v-show="getEditMode() && !this.conceptProps.deprecated"
+          v-b-modal.concept-deprecation-to-search
+        >
+          Deprecate
+          <i class="fa fa-trash"></i>
+        </BButton>
         <BButton
           variant="secondary"
           @click="leaveEditMode()"
@@ -21,6 +29,47 @@
           Done Editing
         </BButton>
 
+        <BModal
+          id="concept-deprecation-to-search"
+          title="Deprecate Concept"
+          size="xl"
+          @ok="deprecateConcept()"
+          ref="deprecate-modal"
+          :ok-disabled="!selectedConcept"
+        >
+          <div class="form-group">
+            <label for="relation-search"
+              >Search and select the concept that replaces
+              "{{ preferredTerm.text }}"</label
+            >
+            <b-form-input
+              v-model="searchTerm"
+              @input="searchConcepts"
+              placeholder="Type to search..."
+            ></b-form-input>
+
+
+            <div v-if="isSearching" class="text-center my-2">
+              <b-spinner small></b-spinner> Searching...
+            </div>
+
+            <div class="search-results mt-2">
+              <div
+                v-for="concept in searchResults"
+                :key="concept.id"
+                class="search-result p-2"
+                :class="{
+                  selected:
+                    selectedConcept && selectedConcept.id === concept.id,
+                }"
+                @click="selectConcept(concept)"
+              >
+                {{ concept.preferred_term.text }}
+              </div>
+            </div>
+          </div>
+        </BModal>
+
         <BModal
           id="exit-confirmation-modal"
           ref="exitModal"
diff --git a/resources/js/components/Concept/mixins/Deprecate.js b/resources/js/components/Concept/mixins/Deprecate.js
new file mode 100644
index 0000000..e85ac52
--- /dev/null
+++ b/resources/js/components/Concept/mixins/Deprecate.js
@@ -0,0 +1,23 @@
+import ConceptService from '../../../api/ConceptService';
+
+export default {
+  methods: {
+    async deprecateConcept() {
+      console.log('Deprecating concept', this.selectedConcept);
+      if (!confirm('This action cannot be undone. Are you sure you want to deprecate?')) {
+        return;
+      }
+      const [error, data] = await ConceptService.deprecateConcept(
+        this.conceptId,
+        this.selectedConcept.id,
+      );
+
+      if (error) {
+        console.error('Failed to deprecate concept:', error);
+        return;
+      }
+      this.flashSuccessAlert();
+      window.location.reload();
+    },
+  },
+};
diff --git a/resources/js/components/Concept/mixins/Term.js b/resources/js/components/Concept/mixins/Term.js
index 1ca464a..4826535 100644
--- a/resources/js/components/Concept/mixins/Term.js
+++ b/resources/js/components/Concept/mixins/Term.js
@@ -3,35 +3,26 @@ import termApi from '../../../api/TermService';
 export default {
   data() {
     return {
-      terms: this.termProps.map(
-        (term, index) => {
-          term.index = index;
-          if('undefined' === typeof term.inEdit){
-            term.inEdit = false;
-          }
-          return term;
-        },
-      ),
+      terms: this.termProps.map((term, index) => {
+        term.index = index;
+        if ('undefined' === typeof term.inEdit) {
+          term.inEdit = false;
+        }
+        return term;
+      }),
       termSearch: [],
       allTermsSearch: false,
     };
   },
   computed: {
     alternateTerms() {
-      return this.terms
-        .filter((term) => !term.preferred)
-        .sort();
+      return this.terms.filter((term) => !term.preferred).sort();
     },
     preferredTerm() {
       return this.terms.find((term) => term.preferred);
     },
     hasEmptyTerm() {
-      return !!(
-        this.terms.length &&
-        !this.terms[
-          this.terms.length - 1
-        ].text
-      );
+      return !!(this.terms.length && !this.terms[this.terms.length - 1].text);
     },
   },
   methods: {
@@ -54,7 +45,7 @@ export default {
     },
     async saveTerm(term, termIndex) {
       const finalize = (term, termIndex) => {
-        if(term.inEdit) {
+        if (term.inEdit) {
           this.cancelInlineEdit(term, termIndex);
         }
 
@@ -136,7 +127,7 @@ export default {
       });
     },
     enableInlineEdit(term, termIndex) {
-      if(!this.isVocabularyEditor){
+      if (!this.isVocabularyEditor) {
         return;
       }
 
@@ -146,6 +137,6 @@ export default {
     cancelInlineEdit(term, termIndex) {
       term.inEdit = false;
       this.$set(this.terms, termIndex, term);
-    }
+    },
   },
 };
diff --git a/routes/api.php b/routes/api.php
index 20cea04..89e6355 100644
--- a/routes/api.php
+++ b/routes/api.php
@@ -19,6 +19,7 @@
     return $request->user();
 });
 
+Route::get('concepts/categories', 'API\ConceptController@categories');
 Route::get('concepts/search', 'API\ConceptController@search');
 Route::get('concepts/reconcile/{id}', 'API\ConceptController@reconcile');
 Route::get('concepts/reconcile', 'API\ConceptController@reconcile');