This study focuses on the recent transformation of the urban fringe in East Asia, drawing on examples from China, Vietnam and the Philippines. It identifies the key dimensions of the land conversion process, including its environmental and social implications. Using a welfare economics perspective, the study: proposes a conceptual framework which relates processes, agents and policies/trends involved in urban expansion; explores the lessons and implications of past experience, identifying key market and policy failures; and proposes a menu of policy options and instruments, drawing on international experience, to address such failures.