This paper reviews the theoretical andpolicy debates behind the global wave of infrastructure services privatization, focusing specifically on water and sanitation services. It explores two questions: first, what is the place ofsocial equity considerations in the rapid spread of privatization endeavors in water supply and sanitation services around the world? Second, why has the water services privatization movement been so much slower to catch on in the United States? Equity in water services is defined along three dimensions: physical access to safe drinking water, economic access or ajfordability, and access to planning and decision makingfor the services. Thepaper briefly reviews cases in France, Great Britain and Argentina, then examines the case of California in more depth, and shows how equity concerns are constructed difef rently in these various settings. After discussing the pricing and regulatory implications of privatization from an equity standpoint, the paper concludes with some directions for further research.