diff --git a/src/Generator/ClassGenerator.php b/src/Generator/ClassGenerator.php
index 3ac3dd23..f00d66ee 100644
--- a/src/Generator/ClassGenerator.php
+++ b/src/Generator/ClassGenerator.php
@@ -2,6 +2,7 @@
 
 namespace Laminas\Code\Generator;
 
+use Laminas\Code\Generator\Exception\InvalidArgumentException;
 use Laminas\Code\Reflection\ClassReflection;
 
 use function array_diff;
@@ -847,6 +848,14 @@ public function addMethodFromGenerator(MethodGenerator $method)
             ));
         }
 
+        if ('__construct' !== $methodName) {
+            foreach ($method->getParameters() as $parameter) {
+                if ($parameter instanceof InInitializerGenerator) {
+                    throw new InvalidArgumentException('In Initializer can only be added to constructor.');
+                }
+            }
+        }
+
         $this->methods[strtolower($methodName)] = $method;
         return $this;
     }
diff --git a/src/Generator/InInitializerGenerator.php b/src/Generator/InInitializerGenerator.php
new file mode 100644
index 00000000..80c50c33
--- /dev/null
+++ b/src/Generator/InInitializerGenerator.php
@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Laminas\Code\Generator;
+
+final class InInitializerGenerator extends ParameterGenerator
+{
+    public const VISIBILITY_PUBLIC = 'public';
+    public const VISIBILITY_PROTECTED = 'protected';
+    public const VISIBILITY_PRIVATE = 'private';
+
+    /** @psalm-var ParameterGenerator::VISIBILITY_* */
+    private string $visibility;
+
+    /**
+     * @psalm-param non-empty-string $name
+     * @psalm-param ?non-empty-string $type
+     * @psalm-param ParameterGenerator::VISIBILITY_* $inInitializer
+     */
+    public function __construct(
+        string $name,
+        ?string $type = null,
+        string $visibility = self::VISIBILITY_PUBLIC,
+        $defaultValue = null,
+        ?int $position = null,
+        bool $passByReference = false
+    ) {
+        parent::__construct(
+            $name,
+            $type,
+            $defaultValue,
+            $position,
+            $passByReference,
+        );
+
+        $this->visibility = $visibility;
+    }
+}
\ No newline at end of file
diff --git a/src/Generator/ObjectGenerator.php b/src/Generator/ObjectGenerator.php
new file mode 100644
index 00000000..cd9255b0
--- /dev/null
+++ b/src/Generator/ObjectGenerator.php
@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Laminas\Code\Generator;
+
+final class ObjectGenerator
+{
+    /**
+     * @psalm-param non-empty-string $className
+     * @psalm-param non-empty-string $constructorName
+     */
+    public function __construct(
+        string $className,
+        array $parameters = [],
+        string $constructorName = '__construct'
+    ){
+    }
+}
\ No newline at end of file
diff --git a/test/Generator/ClassGeneratorTest.php b/test/Generator/ClassGeneratorTest.php
index 9de59b65..d92055b4 100644
--- a/test/Generator/ClassGeneratorTest.php
+++ b/test/Generator/ClassGeneratorTest.php
@@ -8,11 +8,17 @@
 use Laminas\Code\Generator\Exception\ExceptionInterface;
 use Laminas\Code\Generator\Exception\InvalidArgumentException;
 use Laminas\Code\Generator\GeneratorInterface;
+use Laminas\Code\Generator\InInitializerGenerator;
 use Laminas\Code\Generator\MethodGenerator;
+use Laminas\Code\Generator\ObjectGenerator;
+use Laminas\Code\Generator\ParameterGenerator;
 use Laminas\Code\Generator\PropertyGenerator;
+use Laminas\Code\Generator\ValueGenerator;
 use Laminas\Code\Reflection\ClassReflection;
+use Laminas\Code\Reflection\MethodReflection;
 use LaminasTest\Code\TestAsset\FooClass;
 use PHPUnit\Framework\TestCase;
+use ReflectionClass;
 use ReflectionMethod;
 use Serializable;
 use stdClass;
@@ -22,6 +28,8 @@
 use function fclose;
 use function fopen;
 use function key;
+use function self;
+use function uniqid;
 
 /**
  * @group Laminas_Code_Generator
@@ -1313,4 +1321,98 @@ public function testCorrectImplementNames()
         $expected = 'class ClassName implements ClassInterface, GeneratorInterface, \Iteratable';
         self::assertStringContainsString($expected, $classGenerator->generate());
     }
+
+    /** @requires PHP >= 8.1 */
+    public function testGenerateClassWithInInitializer(): void
+    {
+        $classGenerator = new ClassGenerator();
+        $classGenerator->setName('InInitializer');
+
+        $classGenerator->addMethod('__construct', [
+            new InInitializerGenerator('inInitializer', 'string')
+        ]);
+
+        $expectedOutput = <<<EOS
+class InInitializer
+{
+    public function __construct(
+        public string \$inInitializer
+    );
+}
+
+EOS;
+
+        self::assertEquals($expectedOutput, $classGenerator->generate());
+    }
+
+    /** @requires PHP >= 8.1 */
+    public function testGenerateClassWithInInitializerWithDefaultValue(): void
+    {
+        $classGenerator = new ClassGenerator();
+        $classGenerator->setName('InInitializerWithDefaultValue');
+
+        $classGenerator->addMethod('__construct', [
+            new InInitializerGenerator(
+                'inInitializer',
+                'Foo',
+                InInitializerGenerator::VISIBILITY_PRIVATE,
+                new ObjectGenerator(
+                    'Foo',
+                    [
+                        'baz' => 'qux'
+                    ],
+                    'bar',
+                )
+            )
+        ]);
+
+        $expectedOutput = <<<EOS
+class InInitializerWithDefaultValue
+{
+    public function __construct(
+        private Foo \$inInitializer = Foo::bar(baz: 'qux')
+    );
+}
+
+EOS;
+
+        self::assertEquals($expectedOutput, $classGenerator->generate());
+    }
+
+    /** @requires PHP >= 8.1 */
+    public function testClassFromReflectionWithInInitializer(): void
+    {
+        $className = uniqid('ClassWithInInitializer', false);
+
+        eval('namespace ' . __NAMESPACE__ . '; class ' . $className . '{ public function __construct( public string \$inInitializer){} }');
+
+        $classGenerator = ClassGenerator::fromReflection(new ReflectionClass(__NAMESPACE__ . '\\' . $className));
+
+        $expectedOutput = <<<EOS
+class ClassWithInInitializer
+{
+    public function __construct(
+        public string $inInitializer
+    );
+}
+
+EOS;
+
+        self::assertEquals($expectedOutput, $classGenerator->generate());
+    }
+
+    /** @requires PHP >= 8.1 */
+    public function testFailToGenerateClassWithInInitializerOnOtherMethods(): void
+    {
+        $classGenerator = new ClassGenerator();
+        $classGenerator->setName('InInitializerOnOtherMethods');
+
+        $this->expectExceptionObject(
+            new InvalidArgumentException('In Initializer can only be added to constructor.')
+        );
+
+        $classGenerator->addMethod('thisIsNoConstructor', [
+            new InInitializerGenerator('inInitializer', 'string')
+        ]);
+    }
 }