This User's Guide introduces the main concepts underlying PSIA, presents key elements of good practice approaches to PSIA, and highlights some of the main constraints and operational principles for PSIA. It is intended for practitioners undertaking PSIA in developing countries. It does not set out operational policy or guidance to World Bank staff. This User's Guide highlights some of the key tools that practitioners may find useful to analyze poverty and social impacts of policy reforms, but does not aim to be comprehensive in its coverage.