diff --git a/SilMock/Google/Service/Directory/Resource/Members.php b/SilMock/Google/Service/Directory/Resource/Members.php
index 0f5c320..5b56513 100644
--- a/SilMock/Google/Service/Directory/Resource/Members.php
+++ b/SilMock/Google/Service/Directory/Resource/Members.php
@@ -15,6 +15,20 @@ public function __construct(?string $dbFile = null)
         parent::__construct($dbFile, 'directory', 'members');
     }
 
+    public function hasMember(string $groupKey, string $memberKey): array
+    {
+        $members = $this->listMembers($groupKey);
+        $memberList = $members->getMembers();
+        $memberEmailAddresses = [];
+        foreach ($memberList as $member) {
+            $memberEmailAddresses[] = mb_strtolower($member->getEmail());
+        }
+        $isMember = in_array(mb_strtolower($memberKey), $memberEmailAddresses);
+        return [
+            'isMember' => $isMember,
+        ];
+    }
+
     /**
      * @throws Exception
      */
diff --git a/SilMock/tests/Google/Service/Directory/Resource/MembersTest.php b/SilMock/tests/Google/Service/Directory/Resource/MembersTest.php
index 6e57081..95f9ca4 100644
--- a/SilMock/tests/Google/Service/Directory/Resource/MembersTest.php
+++ b/SilMock/tests/Google/Service/Directory/Resource/MembersTest.php
@@ -12,7 +12,7 @@ class MembersTest extends TestCase
     // GroupsTest and MembersTest need to share same DB, also
     // They are very dependent on order run.
     // groups.insert, groups.listGroups, members.insert, members.listMembers
-    public $dataFile = DATAFILE5;
+    public string $dataFile = DATAFILE5;
 
     public function testInsert()
     {
@@ -26,15 +26,32 @@ public function testInsert()
         try {
             $addedMember = $mockGoogleServiceDirectory->members->insert($groupEmailAddress, $member);
         } catch (Exception $exception) {
-            $this->assertFalse(
-                true,
+            self::fail(
                 sprintf(
                     'Was expecting the members.insert method to function, but got: %s',
                     $exception->getMessage()
                 )
             );
         }
-        $this->assertTrue($addedMember instanceof GoogleDirectory_Member);
+        self::assertTrue($addedMember instanceof GoogleDirectory_Member);
+    }
+
+    public function testHasMember()
+    {
+        $groupEmailAddress = 'sample_group@groups.example.com';
+        $mockGoogleServiceDirectory = new GoogleMock_Directory('anyclient', $this->dataFile);
+        try {
+            $result = $mockGoogleServiceDirectory->members->hasMember(
+                $groupEmailAddress,
+                'test@example.com'
+            );
+            $hasMember = $result['isMember'] ?? false;
+        } catch (Exception $exception) {
+            self::fail(
+                $exception->getMessage()
+            );
+        }
+        self::assertTrue($hasMember);
     }
 
     public function testListMembers()
@@ -45,15 +62,14 @@ public function testListMembers()
         try {
             $members = $mockGoogleServiceDirectory->members->listMembers($groupEmailAddress);
         } catch (Exception $exception) {
-            $this->assertFalse(
-                true,
+            self::fail(
                 sprintf(
                     'Was expecting the members.list method to function, but got: %s',
                     $exception->getMessage()
                 )
             );
         }
-        $this->assertNotEmpty(
+        self::assertNotEmpty(
             $members,
             'Was expecting the members.list method to have at least one member.'
         );