diff --git a/README.md b/README.md
index 6025389..4ff314e 100644
--- a/README.md
+++ b/README.md
@@ -32,8 +32,9 @@ Options
 | signatureAlgorithm  | signature algorithm, options: rsa-sha1, rsa-sha256 | ```'rsa-sha256'``` |
 | digestAlgorithm     | digest algorithm, options: sha1, sha256          | ```'sha256'``` |
 | RelayState          | state of the auth process                        | ```req.query.RelayState || req.body.RelayState``` |
-| sessionIndex          | the index of a particular session between the principal identified by the subject and the authenticating authority                        | _SessionIndex is not included_ |
-| responseHandler       | custom response handler for SAML response f(SAMLResponse, options, req, res, next) | HTML response that POSTS to postUrl |
+| sessionIndex        | the index of a particular session between the principal identified by the subject and the authenticating authority                        | _SessionIndex is not included_ |
+| responseHandler     | custom response handler for SAML response f(SAMLResponse, options, req, res, next) | HTML response that POSTS to postUrl |
+| signResponse        | sign the response instead of the assertion       | false |
 
 
 Add the middleware as follows: