This report discusses a research project conducted by the UNT Libraries. The UNT Libraries received a National Leadership Grant from the Institute of Museum and Library Services for a two-year study to redesign the interface to The Portal to Texas History, a digital library program at the UNT Libraries. This report opens with background information for the project, describes the project's methods and working model, guides the reader through the project's three phases and associated feedback from the review process, and presents the revised model for application development. The report closes with measures of the project's success as well as reflections on the experience gained and its value for future digital library application development projects.