An information architecture that allows users to easily navigate through a system and quickly recover from mistakes is often defined as a highly usable system. But usability in systems design goes beyond a good interface and efficient navigation. In this article we describe two database systems in a law enforcement agency. One system is a legacy, text-based system with cumbersome navigation (RMS); the newer system is a graphical user interface with simplified navigation (CopNet). It is hypothesized that law enforcement users will evaluate CopNet higher than RMS, but experts of the older system will evaluate it higher than others will. We conducted two user studies. One study examined what users thought of RMS and CopNet, and compared RMS experts' evaluations with nonexperts. We found that all users evaluated CopNet as more effective, easier to use, and easier to navigate than RMS, and this was especially noticeable for users who were not experts with the older system. The second, follow-up study examined use behavior after CopNet was deployed some time later. The findings revealed that evaluations of CopNet were not associated with its use. If the newer system had a better interface and was easier to navigate than the older, legacy system, why were law enforcement personnel reluctant to switch? We discuss reasons why switching to a new system is difficult, especially for those who are most adept at using the older system. Implications for system design and usability are also discussed.