This article advocates mouse tracking as an emerging method to include in corporate enterprise portal usability assessment. Issues of Web site usability testing are discussed, with mouse tracking as one method that should be given consideration in assessing enterprise portals. Usability testing is part of the process of assessing how well a machine or application does its job. Efficiency is in turn one component of usability, but is perhaps one of the most important components with regard to Web sites that are designed to serve as corporate enterprise portals. An enterprise portal is an organization’s Website that functions to deliver internal employees or external partners or customers to organizational information, applications, or services.