A system and method for client-side authentication for secure Internet communications is disclosed. In one embodiment, an intermediate device receives a web browser secure socket layer certificate from a web browser, authenticates the web browser using the secure socket layer certificate, and then re-signs the secure socket layer certificate with an intermediate device public key and an intermediate device certificate authority signature. The intermediate device sends the re-signed secure socket layer certificate to a web server and the web server authenticates the intermediate device using the re-signed secure socket layer certificate. In another embodiment, an intermediate device receives a web browser secure socket layer certificate from a web browser, inserts the web browser secure socket layer certificate into a HTTP header of a packet, and sends the packet to a web server.