diff --git a/src/Algorithm.php b/src/Algorithm.php
index b35d768..a4825af 100644
--- a/src/Algorithm.php
+++ b/src/Algorithm.php
@@ -14,15 +14,18 @@ abstract class Algorithm
     public static function create($name)
     {
         switch ($name) {
-        case 'hmac-sha1':
-            return new HmacAlgorithm('sha1');
-            break;
-        case 'hmac-sha256':
-            return new HmacAlgorithm('sha256');
-            break;
-        default:
-            throw new Exception("No algorithm named '$name'");
-            break;
+            case 'hmac-sha1':
+                return new HmacAlgorithm('sha1');
+                break;
+            case 'hmac-sha256':
+                return new HmacAlgorithm('sha256');
+                break;
+            case 'rsa-sha512':
+                return new RsaAlgorithm('sha512');
+                break;
+            default:
+                throw new Exception("No algorithm named '$name'");
+                break;
         }
     }
 }
diff --git a/src/RsaAlgorithm.php b/src/RsaAlgorithm.php
new file mode 100644
index 0000000..dcd575e
--- /dev/null
+++ b/src/RsaAlgorithm.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace HttpSignatures;
+
+class RsaAlgorithm implements AlgorithmInterface
+{
+    /** @var string */
+    private $digestName;
+
+    /**
+     * @param string $digestName
+     */
+    public function __construct($digestName)
+    {
+        $this->digestName = $digestName;
+    }
+
+    /**
+     * @return string
+     */
+    public function name()
+    {
+        return sprintf('rsa-%s', $this->digestName);
+    }
+
+    /**
+     * @param string $key
+     * @param string $data
+     *
+     * @return string
+     */
+    public function sign($privateKey, $data)
+    {
+        openssl_sign($data, $signature, $privateKey, 'RSA-SHA512');
+
+        return $signature;
+    }
+}