diff --git a/composer.json b/composer.json
index 11758fe..8af5837 100644
--- a/composer.json
+++ b/composer.json
@@ -16,9 +16,9 @@
         "psr/http-message": "The package containing the PSR-7 interfaces"
     },
     "autoload": {
-        "psr-4": {
-            "Fig\\Http\\Message\\": "src/"
-        }
+        "files": [
+            "constants.php"
+        ]
     },
     "extra": {
         "branch-alias": {
diff --git a/src/StatusCodeInterface.php b/constants.php
similarity index 81%
rename from src/StatusCodeInterface.php
rename to constants.php
index 99b7e78..ba44bf9 100644
--- a/src/StatusCodeInterface.php
+++ b/constants.php
@@ -1,6 +1,38 @@
 <?php
 
-namespace Fig\Http\Message;
+/**
+ * Defines constants for common HTTP request methods.
+ *
+ * Usage:
+ *
+ * <code>
+ * use Fig\Http\Message\Request;
+ *
+ * class RequestFactory
+ * {
+ *     public static function factory(
+ *         $uri = '/',
+ *         $method = Request\METHOD_GET,
+ *         $data = []
+ *     ) {
+ *     }
+ * }
+ * </code>
+ */
+namespace Fig\Http\Message\Request
+{
+    const METHOD_HEAD    = 'HEAD';
+    const METHOD_GET     = 'GET';
+    const METHOD_POST    = 'POST';
+    const METHOD_PUT     = 'PUT';
+    const METHOD_PATCH   = 'PATCH';
+    const METHOD_DELETE  = 'DELETE';
+    const METHOD_PURGE   = 'PURGE';
+    const METHOD_OPTIONS = 'OPTIONS';
+    const METHOD_TRACE   = 'TRACE';
+    const METHOD_CONNECT = 'CONNECT';
+}
+
 
 /**
  * Defines constants for common HTTP status code.
@@ -26,15 +58,17 @@
  * Usage:
  *
  * <code>
- * class ResponseFactory implements StatusCodeInterface
+ * use Fig\Http\Message\Response;
+ *
+ * class ResponseFactory
  * {
- *     public function createResponse($code = self::STATUS_OK)
+ *     public function createResponse($code = Response\STATUS_OK)
  *     {
  *     }
  * }
  * </code>
  */
-interface StatusCodeInterface
+namespace Response
 {
     // Informational 1xx
     const STATUS_CONTINUE = 100;
diff --git a/src/RequestMethodInterface.php b/src/RequestMethodInterface.php
deleted file mode 100644
index 97d9a93..0000000
--- a/src/RequestMethodInterface.php
+++ /dev/null
@@ -1,34 +0,0 @@
-<?php
-
-namespace Fig\Http\Message;
-
-/**
- * Defines constants for common HTTP request methods.
- *
- * Usage:
- *
- * <code>
- * class RequestFactory implements RequestMethodInterface
- * {
- *     public static function factory(
- *         $uri = '/',
- *         $method = self::METHOD_GET,
- *         $data = []
- *     ) {
- *     }
- * }
- * </code>
- */
-interface RequestMethodInterface
-{
-    const METHOD_HEAD    = 'HEAD';
-    const METHOD_GET     = 'GET';
-    const METHOD_POST    = 'POST';
-    const METHOD_PUT     = 'PUT';
-    const METHOD_PATCH   = 'PATCH';
-    const METHOD_DELETE  = 'DELETE';
-    const METHOD_PURGE   = 'PURGE';
-    const METHOD_OPTIONS = 'OPTIONS';
-    const METHOD_TRACE   = 'TRACE';
-    const METHOD_CONNECT = 'CONNECT';
-}