This article describes efforts to create, share, and sustain an online clearing-house of expert-reviewed "promising practices" in pandemic influenza preparedness from September 2006 to December 2008. This project involved six activities: (1) determining focus areas, (2) defining a promising practice, (3) collecting practices, (4) establishing an expert-review process for accepting practices, (5) disseminating the practices, and (6) evaluating the project. By December 31, 2008, materials and descriptions for 181 expert-reviewed practices had been posted in a public online database. Practices were available in four areas: models for care, communication, mitigation, and at-risk groups. The database has been used by international agencies and a variety of U.S. organizations. The challenges and constraints facing the U.S. public health system underscore the need to maximize resources. We believe that the Promising Practices Project demonstrates a useful approach in pandemic preparedness and response and may serve as a valuable model for other areas of public health.