In 2006–07, the Water and Sanitation Program (WSP) initiated research to identify barriers to service delivery for the urban poor. The findings of the research were presented in the Guidance Notes on Improving Water Supply and Sanitation Services to the Urban Poor in India. The Urban Global Practice Team of WSP decided to expand the work to a global context. The Guidance Notes provide a systematic analysis of the barriers to service delivery for the urban poor and recommend practical solutions and strategies to overcome these barriers. The Guidance Notes are based on an in-depth research of various initiatives from Africa, East and South Asia, and Latin America. An accompanying volume, Global Experiences on Expanding Services to the Urban Poor, is a documentation of ‘Global Case Studies’ and ‘Consultations with Urban Poor Communities’.