Client requests may be directed through a secret holding proxy system such that the secret holding proxy system may insert a secret into a client request before arriving at the destination. The insertion of a secret may include inserting a digital signature, token or other information that includes a secret or information based upon a secret, which may include secret exchange or authentication protocols. The secret holding proxy system may also remove secrets and/or transform incoming messages such that the client may transparently receive the underlying content of the message.