The numbers of students with disabilities enrolling in postsecondary institutions has increased since the passage of key disability rights legislation. As a result, the need for information about accommodating postsecondary students with disabilities has increased in the last two decades, especially since the passage of the Higher Education Amendments of 1998. This study used Dick and Carey's (1996) model of instructional design to conduct a formative evaluation of a Web-based performance support system (WPSS) designed for academic administrators, instructional employees, and auxiliary service administrators to enhance accommodations for postsecondary students with disabilities. Formative evaluation consisted of expert review, one-to-one, consumer analysis, and field trial phases. During the expert review phase, subject matter experts, instructional design and usability experts, and individuals with disabilities completed surveys to assess the degree to which the WPSS contained current content, included elements of effective design, and was accessible to individuals with disabilities. During the one-to-one, consumer analysis, and field trial phases, academic administrators, instructional personnel, and auxiliary service administrators on the University of Kentucky campus completed a questionnaire using the WPSS to assess the degree to which the WPSS was effective in providing information. In addition, users completed a survey to assess their perceptions of the WPSS. Finally, data were collected to assess difficulties encountered by users. Results from the expert review phase of the evaluation suggest that the WPSS contained current content, included elements of effective design, and was accessible to individuals with disabilities. Analysis of the questionnaire scores from all phases revealed that users obtained a mean accuracy rate of 74% or higher on the in-session questionnaire. In addition, all users required a mean of 3.9 minutes or less per question to locate responses for items on the questionnaire. The perceptions of all users about the WPSS were positive. Results also indicated that users reported a variety of technical difficulties; however, the majority were related to server errors. Revisions made to the WPSS after each phase of evaluation are described. Implications of the investigation for researchers and Web developers, limitations of the investigation, and areas for future research also are discussed.