This report was developed with the National Decentralized Water Resources Capacity Development Project. It examines how communities consider and value the benefits and costs of onsite, cluster, and centralized wastewater system options in monetary or other terms, and examines the driving issues, motivations, thought processes, and decision-making methods of stakeholders relative to choices of wastewater system scale. Includes case studies of eight U.S. communities and an analysis of the financial benefits of incremental investment in small systems compared to large upfront investments in centralized capacity (December 2004).