Methods and apparatus for determining the integrity of a device. A method is provided for use in a server to provide a dynamic integrity check of a client device. The method includes selecting a selected integrity application from one or more integrity applications, wherein the selected integrity application operates to generate a unique preselected integrity response. The method also includes downloading the selected integrity application for execution on the client device, and receiving a response from the selected integrity application. The method also includes determining whether or not the response is the preselected integrity response.