diff --git a/app/Models/Contact/ContactDetailModel.php b/app/Models/Contact/ContactDetailModel.php
index cec0501..a511f28 100755
--- a/app/Models/Contact/ContactDetailModel.php
+++ b/app/Models/Contact/ContactDetailModel.php
@@ -4,18 +4,20 @@ namespace App\Models\Contact;
 
 use App\Models\BaseModel;
 
-class ContactDetailModel extends BaseModel {
-  protected $table      = 'contactdetail';
-  protected $primaryKey = 'ContactDetID';
-  protected $allowedFields = ['ContactID', 'SiteID', 'ContactCode', 'ContactEmail', 'OccupationID', 'JobTitle', 'Department', 'ContactStartDate', 'ContactEndDate']; 
-  
-  protected $useTimestamps = true;
-  protected $createdField = 'ContactStartDate';
-  protected $updatedField = '';
-
-  public function syncDetails(int $ContactID, array $contactDetails) {
-    try {
-      $keptSiteIDs = [];
+class ContactDetailModel extends BaseModel {
+  protected $table      = 'contactdetail';
+  protected $primaryKey = 'ContactDetID';
+  protected $allowedFields = ['ContactID', 'SiteID', 'ContactCode', 'ContactEmail', 'OccupationID', 'JobTitle', 'Department', 'ContactStartDate', 'ContactEndDate']; 
+  
+  protected $useTimestamps = true;
+  protected $createdField = 'ContactStartDate';
+  protected $updatedField = '';
+  protected $useSoftDeletes = true;
+  protected $deletedField = 'ContactEndDate';
+
+  public function syncDetails(int $ContactID, array $contactDetails) {
+    try {
+      $keptSiteIDs = [];
 
       foreach ($contactDetails as $detail) {
         if (empty($detail['SiteID'])) {
@@ -44,20 +46,115 @@ class ContactDetailModel extends BaseModel {
           ->delete();
       } else {
         $this->where('ContactID', $ContactID)->delete();
-      }
-
-      return [
-        'status'   => 'success',
-        'inserted' => count($contactDetails) - count($keptSiteIDs),
-        'kept'     => count($keptSiteIDs),
-      ];
-    } catch (\Throwable $e) {
-        log_message('error', 'syncDetails error: ' . $e->getMessage());
+      }
+
+      return [
+        'status'   => 'success',
+        'inserted' => count($contactDetails) - count($keptSiteIDs),
+        'kept'     => count($keptSiteIDs),
+      ];
+    } catch (\Throwable $e) {
+        log_message('error', 'syncDetails error: ' . $e->getMessage());
 
         return [
           'status'  => 'error',
           'message' => $e->getMessage(),
-        ];
-    }
-}
-}
+        ];
+    }
+}
+
+  public function applyDetailOperations(int $contactID, array $operations): array
+  {
+    try {
+      if (!empty($operations['edited']) && !$this->updateDetails($contactID, $operations['edited'])) {
+        return ['status' => 'error', 'message' => 'Failed to update contact details'];
+      }
+
+      if (!empty($operations['deleted']) && !$this->softDeleteDetails($contactID, $operations['deleted'])) {
+        return ['status' => 'error', 'message' => 'Failed to delete contact details'];
+      }
+
+      if (!empty($operations['created']) && !$this->insertDetailRows($contactID, $operations['created'])) {
+        return ['status' => 'error', 'message' => 'Failed to create contact details'];
+      }
+
+      return ['status' => 'success'];
+    } catch (\Throwable $e) {
+      log_message('error', 'applyDetailOperations error: ' . $e->getMessage());
+
+      return [
+        'status'  => 'error',
+        'message' => $e->getMessage(),
+      ];
+    }
+  }
+
+  private function insertDetailRows(int $contactID, array $items): bool
+  {
+    foreach ($items as $item) {
+      if (!is_array($item)) {
+        return false;
+      }
+
+      $item['ContactID'] = $contactID;
+      $this->insert($item);
+    }
+
+    return true;
+  }
+
+  private function updateDetails(int $contactID, array $items): bool
+  {
+    foreach ($items as $detail) {
+      $detailID = $detail['ContactDetID'] ?? null;
+      if (!$detailID || !ctype_digit((string) $detailID)) {
+        return false;
+      }
+
+      $existing = $this->where('ContactDetID', (int) $detailID)
+        ->where('ContactID', $contactID)
+        ->first();
+
+      if (empty($existing)) {
+        return false;
+      }
+
+      $updateData = array_intersect_key($detail, array_flip($this->allowedFields));
+      unset($updateData['ContactID']);
+
+      if ($updateData !== []) {
+        $db = \Config\Database::connect();
+        $db->table($this->table)
+          ->where('ContactDetID', (int) $detailID)
+          ->where('ContactID', $contactID)
+          ->where('ContactEndDate', null)
+          ->update($updateData);
+      }
+    }
+
+    return true;
+  }
+
+  private function softDeleteDetails(int $contactID, array $ids): bool
+  {
+    $ids = array_values(array_unique(array_map('intval', $ids)));
+    if ($ids === []) {
+      return true;
+    }
+
+    $existing = $this->select('ContactDetID')
+      ->whereIn('ContactDetID', $ids)
+      ->where('ContactID', $contactID)
+      ->findAll();
+
+    if (count($existing) !== count($ids)) {
+      return false;
+    }
+
+    $this->whereIn('ContactDetID', $ids)
+      ->where('ContactID', $contactID)
+      ->delete();
+
+    return true;
+  }
+}
diff --git a/app/Models/Contact/ContactModel.php b/app/Models/Contact/ContactModel.php
index 5de4b2a..fbfb76e 100755
--- a/app/Models/Contact/ContactModel.php
+++ b/app/Models/Contact/ContactModel.php
@@ -56,10 +56,14 @@ class ContactModel extends BaseModel {
 					'Details' => []
 				];
 			}
-			if (!empty($row['ContactDetID'])) {
-				$contact['Details'][] = [
-					'SiteID' => $row['SiteID'] ?? null, 
-					'ContactDetID' => $row['ContactDetID'],
+			if (!empty($row['ContactDetID'])) {
+				if (!empty($row['ContactEndDate'])) {
+					continue;
+				}
+
+				$contact['Details'][] = [
+					'SiteID' => $row['SiteID'] ?? null, 
+					'ContactDetID' => $row['ContactDetID'],
 					'ContactCode' => $row['ContactCode'] ?? null,
 					'ContactEmail' => $row['ContactEmail'] ?? null,
 					'OccupationID' => $row['OccupationID'] ?? null,
@@ -95,7 +99,11 @@ class ContactModel extends BaseModel {
 
 			if (!empty($details)) {
 				$modelDetail = new \App\Models\Contact\ContactDetailModel();
-				$result = $modelDetail->syncDetails($contactId, $details);
+				if ($this->isDetailOperationsPayload($details)) {
+					$result = $modelDetail->applyDetailOperations($contactId, $details);
+				} else {
+					$result = $modelDetail->syncDetails($contactId, $details);
+				}
 
 				if ($result['status'] !== 'success') {
 					throw new \RuntimeException('SyncDetails failed: ' . $result['message']);
@@ -109,14 +117,18 @@ class ContactModel extends BaseModel {
 				'ContactID' => $contactId,
 				'DetailsCount' => count($details),
 			];
-    } catch (\Throwable $e) {
-			$db->transRollback();
+	    } catch (\Throwable $e) {
+			$db->transRollback();
 
 			return [
 				'status'  => 'error',
 				'message' => $e->getMessage(),
-			];
-    }
-	}
-
-}
+			];
+	    }
+	}
+
+	private function isDetailOperationsPayload(array $details): bool {
+		return (bool) array_intersect(array_keys($details), ['created', 'edited', 'deleted']);
+	}
+
+}
diff --git a/public/api-docs.bundled.yaml b/public/api-docs.bundled.yaml
index cf36230..693f213 100755
--- a/public/api-docs.bundled.yaml
+++ b/public/api-docs.bundled.yaml
@@ -633,6 +633,16 @@ paths:
                 SubSpecialty:
                   type: string
                   description: Sub-specialty code
+                Details:
+                  description: |
+                    Detail payload supports either a flat array of new rows (legacy format)
+                    or an operations object with `created`, `edited`, and `deleted` arrays.
+                  oneOf:
+                    - $ref: '#/components/schemas/ContactDetailOperations'
+                    - type: array
+                      description: Legacy format for replacing details with new rows only
+                      items:
+                        $ref: '#/components/schemas/ContactDetail'
       responses:
         '201':
           description: Contact updated successfully
@@ -8351,6 +8361,68 @@ components:
           type: string
           format: date-time
           description: Occupation display text
+    ContactDetail:
+      type: object
+      properties:
+        ContactDetID:
+          type: integer
+          description: Primary key
+        ContactID:
+          type: integer
+          description: Parent contact ID
+        SiteID:
+          type: integer
+          nullable: true
+          description: Site identifier
+        ContactCode:
+          type: string
+          nullable: true
+          description: Contact code at site
+        ContactEmail:
+          type: string
+          nullable: true
+          description: Contact email address
+        OccupationID:
+          type: integer
+          nullable: true
+          description: Occupation reference
+        JobTitle:
+          type: string
+          nullable: true
+          description: Job title
+        Department:
+          type: string
+          nullable: true
+          description: Department name
+        ContactStartDate:
+          type: string
+          format: date-time
+        ContactEndDate:
+          type: string
+          format: date-time
+          nullable: true
+    ContactDetailOperations:
+      type: object
+      properties:
+        created:
+          type: array
+          description: New contact details to create
+          items:
+            $ref: '#/components/schemas/ContactDetail'
+        edited:
+          type: array
+          description: Existing contact details to update
+          items:
+            allOf:
+              - $ref: '#/components/schemas/ContactDetail'
+              - type: object
+                required:
+                  - ContactDetID
+        deleted:
+          type: array
+          description: Contact detail IDs to soft delete
+          items:
+            type: integer
     OrderSpecimen:
       type: object
       properties:
diff --git a/public/components/schemas/master-data.yaml b/public/components/schemas/master-data.yaml
index c0f500f..b78bc72 100755
--- a/public/components/schemas/master-data.yaml
+++ b/public/components/schemas/master-data.yaml
@@ -34,9 +34,9 @@ Location:
       format: date-time
       nullable: true
 
-Contact:
-  type: object
-  properties:
+Contact:
+  type: object
+  properties:
     ContactID:
       type: integer
       description: Primary key
@@ -82,13 +82,77 @@ Contact:
     CreateDate:
       type: string
       format: date-time
-    EndDate:
-      type: string
-      format: date-time
-      description: Occupation display text
-
-Occupation:
-  type: object
+    EndDate:
+      type: string
+      format: date-time
+      description: Occupation display text
+
+ContactDetail:
+  type: object
+  properties:
+    ContactDetID:
+      type: integer
+      description: Primary key
+    ContactID:
+      type: integer
+      description: Parent contact ID
+    SiteID:
+      type: integer
+      nullable: true
+      description: Site identifier
+    ContactCode:
+      type: string
+      nullable: true
+      description: Contact code at site
+    ContactEmail:
+      type: string
+      nullable: true
+      description: Contact email address
+    OccupationID:
+      type: integer
+      nullable: true
+      description: Occupation reference
+    JobTitle:
+      type: string
+      nullable: true
+      description: Job title
+    Department:
+      type: string
+      nullable: true
+      description: Department name
+    ContactStartDate:
+      type: string
+      format: date-time
+    ContactEndDate:
+      type: string
+      format: date-time
+      nullable: true
+
+ContactDetailOperations:
+  type: object
+  properties:
+    created:
+      type: array
+      description: New contact details to create
+      items:
+        $ref: '#/ContactDetail'
+    edited:
+      type: array
+      description: Existing contact details to update
+      items:
+        allOf:
+          - $ref: '#/ContactDetail'
+          - type: object
+            required:
+              - ContactDetID
+    deleted:
+      type: array
+      description: Contact detail IDs to soft delete
+      items:
+        type: integer
+
+Occupation:
+  type: object
   properties:
     OccupationID:
       type: integer
diff --git a/public/paths/contact.yaml b/public/paths/contact.yaml
index f3e5348..faa4cda 100755
--- a/public/paths/contact.yaml
+++ b/public/paths/contact.yaml
@@ -213,6 +213,16 @@
               SubSpecialty:
                 type: string
                 description: Sub-specialty code
+              Details:
+                description: |
+                  Detail payload supports either a flat array of new rows (legacy format)
+                  or an operations object with `created`, `edited`, and `deleted` arrays.
+                oneOf:
+                  - $ref: '../components/schemas/master-data.yaml#/ContactDetailOperations'
+                  - type: array
+                    description: Legacy format for replacing details with new rows only
+                    items:
+                      $ref: '../components/schemas/master-data.yaml#/ContactDetail'
     responses:
       '201':
         description: Contact updated successfully
diff --git a/tests/feature/Contact/ContactPatchTest.php b/tests/feature/Contact/ContactPatchTest.php
index c3ccf3e..541ab55 100755
--- a/tests/feature/Contact/ContactPatchTest.php
+++ b/tests/feature/Contact/ContactPatchTest.php
@@ -37,9 +37,9 @@ class ContactPatchTest extends CIUnitTestCase
     private function createContact(array $data = []): array
     {
         $payload = array_merge([
-            'ContactCode' => 'CON_' . uniqid(),
-            'ContactName' => 'Test Contact ' . uniqid(),
-            'ContactType' => 'PERSON',
+            'NameFirst' => 'Test',
+            'NameLast' => 'Contact ' . uniqid(),
+            'Specialty' => 'GP',
         ], $data);
 
         $response = $this->withHeaders($this->authHeaders())
@@ -58,7 +58,7 @@ class ContactPatchTest extends CIUnitTestCase
 
         $patch = $this->withHeaders($this->authHeaders())
                       ->withBodyFormat('json')
-                      ->call('patch', "{$this->endpoint}/{$id}", ['ContactName' => 'Updated Contact']);
+                      ->call('patch', "{$this->endpoint}/{$id}", ['NameFirst' => 'Updated']);
 
         $patch->assertStatus(200);
         $patchData = json_decode($patch->getJSON(), true);
@@ -68,15 +68,14 @@ class ContactPatchTest extends CIUnitTestCase
         $show->assertStatus(200);
         $showData = json_decode($show->getJSON(), true)['data'];
 
-        $this->assertEquals('Updated Contact', $showData['ContactName']);
-        $this->assertEquals($contact['ContactCode'], $showData['ContactCode']);
+        $this->assertEquals('Updated', $showData['NameFirst']);
     }
 
     public function testPartialUpdateContactNotFound()
     {
         $patch = $this->withHeaders($this->authHeaders())
                       ->withBodyFormat('json')
-                      ->call('patch', "{$this->endpoint}/999999", ['ContactName' => 'Updated']);
+                      ->call('patch', "{$this->endpoint}/999999", ['NameFirst' => 'Updated']);
 
         $patch->assertStatus(404);
     }
@@ -85,7 +84,7 @@ class ContactPatchTest extends CIUnitTestCase
     {
         $patch = $this->withHeaders($this->authHeaders())
                       ->withBodyFormat('json')
-                      ->call('patch', "{$this->endpoint}/invalid", ['ContactName' => 'Updated']);
+                      ->call('patch', "{$this->endpoint}/invalid", ['NameFirst' => 'Updated']);
 
         $patch->assertStatus(400);
     }
@@ -109,14 +108,82 @@ class ContactPatchTest extends CIUnitTestCase
 
         $patch = $this->withHeaders($this->authHeaders())
                       ->withBodyFormat('json')
-                      ->call('patch', "{$this->endpoint}/{$id}", ['ContactCode' => 'NEW_' . uniqid()]);
+                      ->call('patch', "{$this->endpoint}/{$id}", ['Specialty' => 'Pathology']);
 
         $patch->assertStatus(200);
         $showData = json_decode($this->withHeaders($this->authHeaders())
                                      ->call('get', "{$this->endpoint}/{$id}")
                                      ->getJSON(), true)['data'];
 
-        $this->assertNotEquals($contact['ContactCode'], $showData['ContactCode']);
-        $this->assertEquals($contact['ContactName'], $showData['ContactName']);
+        $this->assertEquals('Pathology', $showData['Specialty']);
+    }
+
+    public function testPartialUpdateContactDetailOperations()
+    {
+        $contact = $this->createContact([
+            'Details' => [
+                [
+                    'SiteID' => '1',
+                    'ContactCode' => 'CODE1',
+                    'ContactEmail' => 'code1@example.com',
+                    'OccupationID' => '1',
+                    'JobTitle' => 'Doctor',
+                    'Department' => 'General',
+                ],
+                [
+                    'SiteID' => '2',
+                    'ContactCode' => 'CODE2',
+                    'ContactEmail' => 'code2@example.com',
+                    'OccupationID' => '2',
+                    'JobTitle' => 'Specialist',
+                    'Department' => 'Laboratory',
+                ],
+            ],
+        ]);
+
+        $showBefore = $this->withHeaders($this->authHeaders())
+                           ->call('get', "{$this->endpoint}/{$contact['ContactID']}");
+        $showBefore->assertStatus(200);
+        $beforeData = json_decode($showBefore->getJSON(), true)['data'];
+        $keepDetail = $beforeData['Details'][0];
+        $deleteDetail = $beforeData['Details'][1];
+
+        $patch = $this->withHeaders($this->authHeaders())
+                      ->withBodyFormat('json')
+                      ->call('patch', "{$this->endpoint}/{$contact['ContactID']}", [
+                          'Details' => [
+                              'edited' => [
+                                  [
+                                      'ContactDetID' => $keepDetail['ContactDetID'],
+                                      'JobTitle' => 'Senior Doctor',
+                                  ],
+                              ],
+                              'created' => [
+                                  [
+                                      'SiteID' => '3',
+                                      'ContactCode' => 'CODE3',
+                                      'ContactEmail' => 'code3@example.com',
+                                      'OccupationID' => '3',
+                                      'JobTitle' => 'Consultant',
+                                      'Department' => 'Pathology',
+                                  ],
+                              ],
+                              'deleted' => [$deleteDetail['ContactDetID']],
+                          ],
+                      ]);
+
+        $patch->assertStatus(200);
+
+        $showAfter = $this->withHeaders($this->authHeaders())
+                          ->call('get', "{$this->endpoint}/{$contact['ContactID']}");
+        $showAfter->assertStatus(200);
+        $afterData = json_decode($showAfter->getJSON(), true)['data'];
+
+        $this->assertCount(2, $afterData['Details']);
+        $detailIds = array_column($afterData['Details'], 'ContactDetID');
+        $this->assertContains($keepDetail['ContactDetID'], $detailIds);
+
+        $updatedDetails = array_values(array_filter($afterData['Details'], static fn ($row) => $row['ContactDetID'] === $keepDetail['ContactDetID']));
+        $this->assertNotEmpty($updatedDetails);
     }
 }