A system and method is disclosed for collecting website visitor activity for profiling visitor interests and dynamically modifying the content of the website to better match the visitor's profile. The visitor activity data is collected directly from the visitor's client browser or from the website's own web log information. The collected data consists of the page identifier, page links, and the previous page identifier. Similarly, the modified page content can be sent directly to the client browser or can be sent back to the website server for integration with the other page content. The collected data is stored in a database. Based on the amount of information collected on the visitor and the various items that are presented on the website, the visitors and items are profiled so that a visitor's response to other items can be predicted and recommended to the visitor. The recommendations can be requested and displayed directly by and to the client browser or the website server can make the request and subsequently display the matching content. The system has application in personalization, behavioral targeting, Internet retailing, social networking, affiliate marketing, and online advertising, to name but a few applications.