This workbook was produced in order to test and adapt the World Commission on Protected Areas (WCPA) methodologies for use at marine protected areas (MPAs) in the Western Indian Ocean. The workbook is designed to allow for a dynamic process of MPA management based on the lessons learnt from pilot assessments in Kenya, Tanzania and the Seychelles. The method takes into account the management issues faced in the Western Indian Ocean, is cost effective, and encourages self-assessment by the managers. It is intended that the management effectiveness workbook serve as a practical tool in assisting MPA managers and practitioners in their role as custodians of marine biodiversity in the Western Indian Ocean.