This study describes usability testing of four subject guides (created using LibGuides) at Duke University. Subjects completed two tasks for each guide, then were asked to rate the ease of use of the guide, as well as elaborate on features that made the guide difficult to use and easy to use, and make suggestions to improve usability of the guide. Despite the high failure rate of many of the tasks, the guides were generally perceived as easy to use. Features identified as facilitators to use were clearly labeled tabs, organization of resources within boxes, descriptions of resources, and clearly labeled boxes. Features identified as barriers to use were the inclusion of too many resources, lack of instruction on using guides, and lack of resource description. Subjects expressed a desire for instruction on using guides, description of resources, tables of contents, and a “Getting Started” tab to orient users.