1. A web page preview system; in which the system comprises a web host for providing both a first version and a second version of a set of web pages in a nm-time environment; and an interface for receiving requests from users for access to the different versions of the set of web pages; in which the system is arranged in use to provide access to the first version of the set of web pages in the run-time environment to a general set of users; and in which the system is arranged in use to provide access to the second version of the set of web pages in the run-time environment to a restricted sub-set of users; so that the second version of the set of web pages may be previewed in the run-time environment by the restricted sub-set of users.