The coastal waters of Southeast Asian countries have some of the world's richest ecosystems characterized by extensive coral reefs and dense mangrove forests. The publication provides insights useful towards a better understanding of the seagrass ecosystem, its frailties and strengths in the face of acute coastal environment stresses. Details are also given of some common regional constraints that hamper full utilization of the seagrassecosystem and a plan of action towards sustainable development of this ecosystem's resources is proposed.