Non-potable and potable (principally in-direct potable) water reuse initiatives in the United States have faced increasing public opposition. Several high-profile initiatives have been halted after several years of planning and tremendous expenditures. To understand why the public holds the perceptions they do and what public participation options exist to address water reuse more constructively, a multidisciplinary analysis was undertaken by a team of social scientists, engineers, and water professionals. Through a comprehensive literature review, three in-depth case studies, and a 2-day interactive symposium this framework was developed for water professionals. The framework summarizes five underlying principles that contribute to shaping public perception and acts as a guide for water professionals in their selection of public outreach, education, and participation activities. Adhering to the principles outlined in this report contributes to building public confidence and trust, which in turn helps water utilities engage constructively with the public on challenging, contentious issues. The five principles are: ? Manage information for all ? Maintain individual motivation and demonstrate organizational commitment ? Promote communication and public dialog ? Ensure fair and sound decision making and decisions ? Build and maintain trust However, no checklist of "to-do's" exists for establishing public confidence and trust. Quite the opposite, this research suggests that a one-size-fits-all model cannot work because the most appropriate ways to achieve the principles can vary from case to case. Thus, the framework includes an analytical structure to assess the community in which a water reuse initiative is underway. Using diagnostic questions and analytical techniques, a comprehensive picture of the community can be generated and monitored over time. Through application of the diagnostic tools and a commitment to the principles outlined above, water professionals can build the public confidence and trust they need to engage with the public on difficult water reuse issues.