This book explores the increasing impacts on the world's oceans from coastal and offshore development, overfishing, a changing climate, natural events, and other sources that are straining the health of marine ecosystems and the Great lakes. Impacts to these intricately balanced environments include declining fish populations, degradation of coral reefs and other vital habitats, threats to rare or endangered species, and loss of artefacts and resources that represent the diverse cultural heritage of the United States. In the United States and around the world, marine protected areas (MPAs) are increasingly recognised as an important and promising management tool for mitigating or buffering some of these impacts. This book examines the use of MPAs as a way to restore and maintain healthy marine and Great Lakes environments by contributing to the overall protection of critical marine habitats and resources. This is an edited, excerpted and augmented edition of various government publications.