diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index 4d68d07..7008dfd 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -3,6 +3,7 @@
   <file src="src/CacheSessionPersistence.php">
     <MixedArgumentTypeCoercion>
       <code>$sessionData</code>
+      <code><![CDATA[$session->toArray()]]></code>
     </MixedArgumentTypeCoercion>
     <MixedInferredReturnType>
       <code>array</code>
@@ -14,6 +15,9 @@
     <UnusedProperty>
       <code>$persistent</code>
     </UnusedProperty>
+    <UndefinedInterfaceMethod>
+      <code>getId</code>
+    </UndefinedInterfaceMethod>
   </file>
   <file src="src/CacheSessionPersistenceFactory.php">
     <MixedArgument>
@@ -70,5 +74,10 @@
       <code>cacheHeaders</code>
       <code>validCacheLimiters</code>
     </PossiblyUnusedMethod>
+    <UndefinedInterfaceMethod>
+      <code>getId</code>
+      <code>getId</code>
+      <code>getId</code>
+    </UndefinedInterfaceMethod>
   </file>
 </files>
diff --git a/src/CacheSessionPersistence.php b/src/CacheSessionPersistence.php
index 13f3c27..c27c77a 100644
--- a/src/CacheSessionPersistence.php
+++ b/src/CacheSessionPersistence.php
@@ -4,6 +4,7 @@
 
 namespace Mezzio\Session\Cache;
 
+use Mezzio\Session\InitializePersistenceIdInterface;
 use Mezzio\Session\Persistence\CacheHeadersGeneratorTrait;
 use Mezzio\Session\Persistence\Http;
 use Mezzio\Session\Persistence\SessionCookieAwareTrait;
@@ -26,7 +27,7 @@
  * During persistence, if the session regeneration flag is true, a new session
  * identifier is created, and the session re-started.
  */
-class CacheSessionPersistence implements SessionPersistenceInterface
+class CacheSessionPersistence implements InitializePersistenceIdInterface, SessionPersistenceInterface
 {
     use CacheHeadersGeneratorTrait;
     use SessionCookieAwareTrait;
@@ -197,4 +198,13 @@ private function persistSessionDataToCache(string $id, array $data): void
         $item->expiresAfter($this->cacheExpire);
         $this->cache->save($item);
     }
+
+    public function initializeId(SessionInterface $session): SessionInterface
+    {
+        if ($session->getId() === '' || $session->isRegenerated()) {
+            $session = new Session($session->toArray(), $this->generateSessionId());
+        }
+
+        return $session;
+    }
 }
diff --git a/test/CacheSessionPersistenceTest.php b/test/CacheSessionPersistenceTest.php
index 8d88d25..472fc3d 100644
--- a/test/CacheSessionPersistenceTest.php
+++ b/test/CacheSessionPersistenceTest.php
@@ -956,4 +956,45 @@ public function testPersistenceDurationInSessionDataWithValueOfZeroIgnoresGlobal
         $this->assertNotSame($response, $result);
         $this->assertCookieHasNoExpiryDirective($result);
     }
+
+    public function testInitializeIdReturnsSessionWithId(): void
+    {
+        $persistence = new CacheSessionPersistence(
+            $this->cachePool,
+            'test',
+        );
+        $session     = new Session(['foo' => 'bar']);
+        $actual      = $persistence->initializeId($session);
+
+        $this->assertNotSame($session, $actual);
+        $this->assertNotEmpty($actual->getId());
+        $this->assertSame(['foo' => 'bar'], $actual->toArray());
+    }
+
+    public function testInitializeIdRegeneratesSessionId(): void
+    {
+        $persistence = new CacheSessionPersistence(
+            $this->cachePool,
+            'test',
+        );
+        $session     = new Session(['foo' => 'bar'], 'original-id');
+        $session     = $session->regenerate();
+        $actual      = $persistence->initializeId($session);
+
+        $this->assertNotEmpty($actual->getId());
+        $this->assertNotSame('original-id', $actual->getId());
+        $this->assertFalse($actual->isRegenerated());
+    }
+
+    public function testInitializeIdReturnsSessionUnaltered(): void
+    {
+        $persistence = new CacheSessionPersistence(
+            $this->cachePool,
+            'test',
+        );
+        $session     = new Session(['foo' => 'bar'], 'original-id');
+        $actual      = $persistence->initializeId($session);
+
+        $this->assertSame($session, $actual);
+    }
 }