In this volume marine experts from countries of East Africa and southern Asia describe the conditions of marine resources of the large marine ecosystems of the Indian Ocean. Countries of the region represent over a quarter of the world's population, most of whom are existing at or below the poverty level. The potentials for economic growth through the development of coastal tourism, mariculture, fisheries, mineral extraction, and oil and gas production are examined by the authors in relation to the need for ensuring the long-term sustainability of marine resources. Case studies of resource assessments presented by several authors illustrate the magnitude of risk from continuing degradation of resources under the prevailing unmanaged conditions extending over much of coastal areas of East Africa and southern Asia. The authors explore the application of multidisciplinary ecosystem-based assessment and management strategies to the future economic development of the large marine ecosystems of the region. With the initiation of science-based management practcies, the ecosystems of the area can provide an important source of economic growth, improved food security, and nutritional benefits to the populations of stakeholders in coastal areas bordering the Indian Ocean