Abstract: Isolating an iframe of a webpage. In one embodiment, a method may include targeting an iframe in a webpage for isolation, executing, in a server browser, iframe code, sending, from the remote isolation server to the local client, the webpage with the iframe code of the iframe replaced with isolation code, executing, in a client browser, webpage code and the isolation code, intercepting, in the client browser, webpage messages sent from the webpage code and intended to be delivered to the iframe, sending, to the remote isolation server, the intercepted webpage messages to be injected into the iframe code executing at the server browser, intercepting, at the server browser, iframe messages sent from the iframe code and intended to be delivered to the webpage, and sending, to the local client, the intercepted iframe messages to be injected into the webpage code executing at the client browser.