diff --git a/src/Exception/JsonException.php b/src/Exception/JsonException.php
new file mode 100644
index 0000000..b9765ba
--- /dev/null
+++ b/src/Exception/JsonException.php
@@ -0,0 +1,51 @@
+<?php declare(strict_types=1);
+
+/**
+ * It's free open-source software released under the MIT License.
+ *
+ * @author Anatoly Fenric <anatoly@fenric.ru>
+ * @copyright Copyright (c) 2018, Anatoly Fenric
+ * @license https://github.com/sunrise-php/http-message/blob/master/LICENSE
+ * @link https://github.com/sunrise-php/http-message
+ */
+
+namespace Sunrise\Http\Message\Exception;
+
+/**
+ * Import classes
+ */
+use RuntimeException;
+
+/**
+ * Import functions
+ */
+use function json_last_error;
+use function json_last_error_msg;
+
+/**
+ * Import constants
+ */
+use const JSON_ERROR_NONE;
+
+/**
+ * JsonException
+ */
+class JsonException extends RuntimeException
+{
+
+	/**
+	 * @return void
+	 *
+	 * @throws self
+	 */
+	public static function assert() : void
+	{
+		$code = json_last_error();
+
+		if (JSON_ERROR_NONE === $code) {
+			return;
+		}
+
+		throw new self(json_last_error_msg(), $code);
+	}
+}
diff --git a/src/Message.php b/src/Message.php
index 6921b26..7939b80 100644
--- a/src/Message.php
+++ b/src/Message.php
@@ -95,8 +95,7 @@ public function getHeader($name) : array
 	{
 		$name = $this->normalizeHeaderName($name);
 
-		if (empty($this->headers[$name]))
-		{
+		if (empty($this->headers[$name])) {
 			return [];
 		}
 
@@ -110,8 +109,7 @@ public function getHeaderLine($name) : string
 	{
 		$name = $this->normalizeHeaderName($name);
 
-		if (empty($this->headers[$name]))
-		{
+		if (empty($this->headers[$name])) {
 			return '';
 		}
 
@@ -121,7 +119,7 @@ public function getHeaderLine($name) : string
 	/**
 	 * {@inheritDoc}
 	 */
-	public function withHeader($name, $value) : MessageInterface
+	public function withHeader($name, $value, bool $append = false) : MessageInterface
 	{
 		$this->validateHeaderName($name);
 		$this->validateHeaderValue($value);
@@ -129,6 +127,10 @@ public function withHeader($name, $value) : MessageInterface
 		$name = $this->normalizeHeaderName($name);
 		$value = $this->normalizeHeaderValue($value);
 
+		if (isset($this->headers[$name]) && $append) {
+			$value = \array_merge($this->headers[$name], $value);
+		}
+
 		$clone = clone $this;
 
 		$clone->headers[$name] = $value;
@@ -141,22 +143,28 @@ public function withHeader($name, $value) : MessageInterface
 	 */
 	public function withAddedHeader($name, $value) : MessageInterface
 	{
-		$this->validateHeaderName($name);
-		$this->validateHeaderValue($value);
+		return $this->withHeader($name, $value, true);
+	}
 
-		$name = $this->normalizeHeaderName($name);
-		$value = $this->normalizeHeaderValue($value);
+	/**
+	 * Returns a new instance with the given headers
+	 *
+	 * @param iterable $headers
+	 * @param bool $append
+	 *
+	 * @return MessageInterface
+	 *
+	 * @since 1.3.0
+	 */
+	public function withMultipleHeaders(iterable $headers, bool $append = false) : MessageInterface
+	{
+		$result = clone $this;
 
-		if (! empty($this->headers[$name]))
-		{
-			$value = \array_merge($this->headers[$name], $value);
+		foreach ($headers as $name => $value) {
+			$result = $result->withHeader($name, $value, $append);
 		}
 
-		$clone = clone $this;
-
-		$clone->headers[$name] = $value;
-
-		return $clone;
+		return $result;
 	}
 
 	/**
@@ -207,13 +215,14 @@ public function withBody(StreamInterface $body) : MessageInterface
 	 */
 	protected function validateProtocolVersion($protocolVersion) : void
 	{
-		if (! \is_string($protocolVersion))
-		{
+		if (! \is_string($protocolVersion)) {
 			throw new \InvalidArgumentException('HTTP protocol version must be a string');
 		}
-		else if (! \preg_match('/^\d(?:\.\d)?$/', $protocolVersion))
-		{
-			throw new \InvalidArgumentException(\sprintf('The given protocol version "%s" is not valid', $protocolVersion));
+
+		if (! \preg_match('/^\d(?:\.\d)?$/', $protocolVersion)) {
+			throw new \InvalidArgumentException(
+				\sprintf('The given protocol version "%s" is not valid', $protocolVersion)
+			);
 		}
 	}
 
@@ -230,13 +239,14 @@ protected function validateProtocolVersion($protocolVersion) : void
 	 */
 	protected function validateHeaderName($headerName) : void
 	{
-		if (! \is_string($headerName))
-		{
+		if (! \is_string($headerName)) {
 			throw new \InvalidArgumentException('Header name must be a string');
 		}
-		else if (! \preg_match(HeaderInterface::RFC7230_TOKEN, $headerName))
-		{
-			throw new \InvalidArgumentException(\sprintf('The given header name "%s" is not valid', $headerName));
+
+		if (! \preg_match(HeaderInterface::RFC7230_TOKEN, $headerName)) {
+			throw new \InvalidArgumentException(
+				\sprintf('The given header name "%s" is not valid', $headerName)
+			);
 		}
 	}
 
@@ -253,25 +263,23 @@ protected function validateHeaderName($headerName) : void
 	 */
 	protected function validateHeaderValue($headerValue) : void
 	{
-		if (\is_string($headerValue))
-		{
+		if (\is_string($headerValue)) {
 			$headerValue = [$headerValue];
 		}
 
-		if (! \is_array($headerValue) || [] === $headerValue)
-		{
+		if (! \is_array($headerValue) || [] === $headerValue) {
 			throw new \InvalidArgumentException('Header value must be a string or not an empty array');
 		}
 
-		foreach ($headerValue as $oneOf)
-		{
-			if (! \is_string($oneOf))
-			{
+		foreach ($headerValue as $oneOf) {
+			if (! \is_string($oneOf)) {
 				throw new \InvalidArgumentException('Header value must be a string or an array containing only strings');
 			}
-			else if (! \preg_match(HeaderInterface::RFC7230_FIELD_VALUE, $oneOf))
-			{
-				throw new \InvalidArgumentException(\sprintf('The given header value "%s" is not valid', $oneOf));
+
+			if (! \preg_match(HeaderInterface::RFC7230_FIELD_VALUE, $oneOf)) {
+				throw new \InvalidArgumentException(
+					\sprintf('The given header value "%s" is not valid', $oneOf)
+				);
 			}
 		}
 	}
@@ -303,7 +311,6 @@ protected function normalizeHeaderName($headerName) : string
 	protected function normalizeHeaderValue($headerValue) : array
 	{
 		$headerValue = (array) $headerValue;
-
 		$headerValue = \array_values($headerValue);
 
 		return $headerValue;
diff --git a/src/ResponseFactory.php b/src/ResponseFactory.php
index 177d37d..8206231 100644
--- a/src/ResponseFactory.php
+++ b/src/ResponseFactory.php
@@ -53,8 +53,10 @@ public function createResponse(int $code = 200, string $reasonPhrase = '') : Res
 	 */
 	public function createHtmlResponse(int $status, $content) : ResponseInterface
 	{
+		$content = (string) $content;
+
 		$body = (new StreamFactory)->createStream();
-		$body->write((string) $content);
+		$body->write($content);
 
 		return (new Response)
 		->withStatus($status)
@@ -63,22 +65,32 @@ public function createHtmlResponse(int $status, $content) : ResponseInterface
 	}
 
 	/**
-	 * Creates a JSON response object
+	 * Creates a JSON response instance
 	 *
 	 * @param int $status
 	 * @param mixed $payload
 	 * @param int $options
+	 * @param int $depth
 	 *
 	 * @return ResponseInterface
+	 *
+	 * @throws Exception\JsonException
 	 */
-	public function createJsonResponse(int $status, $payload, int $options = 0) : ResponseInterface
+	public function createJsonResponse(int $status, $payload, int $options = 0, int $depth = 512) : ResponseInterface
 	{
+		// clears a previous error...
+		json_encode(null);
+
+		$content = json_encode($payload, $options, $depth);
+
+		Exception\JsonException::assert();
+
 		$body = (new StreamFactory)->createStream();
-		$body->write(json_encode($payload, $options));
+		$body->write($content);
 
 		return (new Response)
 		->withStatus($status)
-		->withHeader('Content-Type', 'application/json')
+		->withHeader('Content-Type', 'application/json; charset=utf-8')
 		->withBody($body);
 	}
 }
diff --git a/tests/MessageTest.php b/tests/MessageTest.php
index 90e7634..d1d5af9 100644
--- a/tests/MessageTest.php
+++ b/tests/MessageTest.php
@@ -180,6 +180,27 @@ public function testAddInvalidHeaderValueInArray($headerValue)
 		(new Message)->withAddedHeader('x-foo', ['bar', $headerValue, 'baz']);
 	}
 
+	public function testWithMultipleHeaders() : void
+	{
+		$message = new Message();
+
+		$subject = $message
+		->withMultipleHeaders(['x-foo' => 'bar'])
+		->withMultipleHeaders(['x-foo' => 'baz']);
+
+		$this->assertNotSame($subject, $message);
+		$this->assertCount(0, $message->getHeaders());
+		$this->assertSame(['x-foo' => ['baz']], $subject->getHeaders());
+
+		$subject = $message
+		->withMultipleHeaders(['x-foo' => 'bar'], true)
+		->withMultipleHeaders(['x-foo' => 'baz'], true);
+
+		$this->assertNotSame($subject, $message);
+		$this->assertCount(0, $message->getHeaders());
+		$this->assertSame(['x-foo' => ['bar', 'baz']], $subject->getHeaders());
+	}
+
 	public function testDeleteHeader()
 	{
 		$mess = (new Message)->withHeader('x-foo', 'bar');
diff --git a/tests/ResponseFactoryTest.php b/tests/ResponseFactoryTest.php
index 0b68470..8ba4f01 100644
--- a/tests/ResponseFactoryTest.php
+++ b/tests/ResponseFactoryTest.php
@@ -9,6 +9,7 @@
 use Psr\Http\Message\ResponseFactoryInterface;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\StreamInterface;
+use Sunrise\Http\Message\Exception\JsonException;
 use Sunrise\Http\Message\ResponseFactory;
 
 /**
@@ -89,7 +90,19 @@ public function testCreateJsonResponse() : void
 
 		$this->assertInstanceOf(ResponseInterface::class, $response);
 		$this->assertSame(400, $response->getStatusCode());
-		$this->assertSame('application/json', $response->getHeaderLine('Content-Type'));
+		$this->assertSame('application/json; charset=utf-8', $response->getHeaderLine('Content-Type'));
 		$this->assertSame(json_encode($payload, $options), (string) $response->getBody());
 	}
+
+	/**
+	 * @return void
+	 */
+	public function testCreateResponseWithInvalidJson() : void
+	{
+		$this->expectException(JsonException::class);
+		$this->expectExceptionMessage('Maximum stack depth exceeded');
+
+		$response = (new ResponseFactory)
+		->createJsonResponse(200, [[]], 0, 1);
+	}
 }