This report describes the USAID Water, Sanitation and Hygiene Finance (WASH-FIN) program’s experience providing investor readiness support to companies pioneering utility-scale sanitation treatment technology solutions in urban settings in Senegal, Kenya, and India. As sanitation is a public good, the report highlights the crucial role of the public sector in market creation for treatment technologies and services. It takes a critical look at the linkages between the public and private sectors in fostering a coherent and efficient marketplace for appropriate technologies. The focus is on treatment technologies applied at utility-scale versus on-site or household solutions, and reflections on the practical experience of providing technical assistance to this limited set of firms. Key challenges and lessons learned are documented.