Environmentally and socially sustainable policies are essential for good governance. Strategic Environmental Assessment (SEA) is the key tool for integrating environmental considerations into policies, programs and plans. This book focuses on SEA applied to policies. Through lessons learned from previous use of SEA on policies, it draws lessons on the strengths and weaknesses of current SEA methodology. It then goes on to analyze how policies are formulated and implemented and proposes a new conceptual framework for conducting SEA of policies that potentially could be more useful in influencing decision makers to integrate environmental sustainability considerations into policy formulation and implementation.