diff --git a/src/StatusCodeInterface.php b/src/StatusCodeInterface.php
new file mode 100644
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+++ b/src/StatusCodeInterface.php
@@ -0,0 +1,100 @@
+<?php
+
+namespace Fig\Http\Message;
+
+/**
+ * Defines constants for common HTTP status code.
+ *
+ * @see https://tools.ietf.org/html/rfc2518#section-9.7
+ * @see https://tools.ietf.org/html/rfc2295#section-8.1
+ * @see https://tools.ietf.org/html/rfc2774#section-7
+ * @see https://tools.ietf.org/html/rfc3229#section-10.4
+ * @see https://tools.ietf.org/html/rfc4918#section-11
+ * @see https://tools.ietf.org/html/rfc5842#section-7.1
+ * @see https://tools.ietf.org/html/rfc5842#section-7.2
+ * @see https://tools.ietf.org/html/rfc6585#section-3
+ * @see https://tools.ietf.org/html/rfc6585#section-4
+ * @see https://tools.ietf.org/html/rfc6585#section-5
+ * @see https://tools.ietf.org/html/rfc6585#section-6
+ * @see https://tools.ietf.org/html/rfc7231#section-6
+ * @see https://tools.ietf.org/html/rfc7238#section-3
+ * @see https://tools.ietf.org/html/rfc7725#section-3
+ *
+ * Usage:
+ *
+ * <code>
+ * class ResponseFactory implements StatusCodeInterface
+ * {
+ *     public function createResponse($code = self::STATUS_OK)
+ *     {
+ *     }
+ * }
+ * </code>
+ */
+interface StatusCodeInterface
+{
+    //Informational 1xx
+    const STATUS_CONTINUE = 100;
+    const STATUS_SWITCHING_PROTOCOLS = 101;
+    const STATUS_PROCESSING = 102;
+    //Successful 2xx
+    const STATUS_OK = 200;
+    const STATUS_CREATED = 201;
+    const STATUS_ACCEPTED = 202;
+    const STATUS_NON_AUTHORITATIVE_INFORMATION = 203;
+    const STATUS_NO_CONTENT = 204;
+    const STATUS_RESET_CONTENT = 205;
+    const STATUS_PARTIAL_CONTENT = 206;
+    const STATUS_MULTI_STATUS = 207;
+    const STATUS_ALREADY_REPORTED = 208;
+    const STATUS_IM_USED = 226;
+    //Redirection 3xx
+    const STATUS_MULTIPLE_CHOICES = 300;
+    const STATUS_MOVED_PERMANENTLY = 301;
+    const STATUS_FOUND = 302;
+    const STATUS_SEE_OTHER = 303;
+    const STATUS_NOT_MODIFIED = 304;
+    const STATUS_USE_PROXY = 305;
+    const STATUS_RESERVED = 306;
+    const STATUS_TEMPORARY_REDIRECT = 307;
+    const STATUS_PERMANENT_REDIRECT = 308;
+    //Client Error 4xx
+    const STATUS_BAD_REQUEST = 400;
+    const STATUS_UNAUTHORIZED = 401;
+    const STATUS_PAYMENT_REQUIRED = 402;
+    const STATUS_FORBIDDEN = 403;
+    const STATUS_NOT_FOUND = 404;
+    const STATUS_METHOD_NOT_ALLOWED = 405;
+    const STATUS_NOT_ACCEPTABLE = 406;
+    const STATUS_PROXY_AUTHENTICATION_REQUIRED = 407;
+    const STATUS_REQUEST_TIMEOUT = 408;
+    const STATUS_CONFLICT = 409;
+    const STATUS_GONE = 410;
+    const STATUS_LENGTH_REQUIRED = 411;
+    const STATUS_PRECONDITION_FAILED = 412;
+    const STATUS_PAYLOAD_TOO_LARGE = 413;
+    const STATUS_URI_TOO_LONG = 414;
+    const STATUS_UNSUPPORTED_MEDIA_TYPE = 415;
+    const STATUS_RANGE_NOT_SATISFIABLE = 416;
+    const STATUS_EXPECTATION_FAILED = 417;
+    const STATUS_UNPROCESSABLE_ENTITY = 422;
+    const STATUS_LOCKED = 423;
+    const STATUS_FAILED_DEPENDENCY = 424;
+    const STATUS_UPGRADE_REQUIRED = 426;
+    const STATUS_PRECONDITION_REQUIRED = 428;
+    const STATUS_TOO_MANY_REQUESTS = 429;
+    const STATUS_REQUEST_HEADER_FIELDS_TOO_LARGE = 431;
+    const STATUS_UNAVAILABLE_FOR_LEGAL_REASONS = 451;
+    //Server Error 5xx
+    const STATUS_INTERNAL_SERVER_ERROR = 500;
+    const STATUS_NOT_IMPLEMENTED = 501;
+    const STATUS_BAD_GATEWAY = 502;
+    const STATUS_SERVICE_UNAVAILABLE = 503;
+    const STATUS_GATEWAY_TIMEOUT = 504;
+    const STATUS_VERSION_NOT_SUPPORTED = 505;
+    const STATUS_VARIANT_ALSO_NEGOTIATES = 506;
+    const STATUS_INSUFFICIENT_STORAGE = 507;
+    const STATUS_LOOP_DETECTED = 508;
+    const STATUS_NOT_EXTENDED = 510;
+    const STATUS_NETWORK_AUTHENTICATION_REQUIRED = 511;
+}