At the beginning of the twenty-first century renewed emphasis on the Reef as a World Heritage Area has come to dominate planning and management, with a heightened recognition of the social and economic implications of World Heritage listing and the interrelationships between natural and cultural heritage. Underlying this is an increasing awareness, formed during the final decades of the twentieth century, that the Reef and its hinterland must be regarded as a dynamic ecosystem: dealing with environmental issues as localised problems on an individual basis is no longer an adequate basis for policy. Faced with continued population growth, mounting tourist traffic and rapid expansion of urbanisation and commercial infrastructure, forward looking planners recognise that the entire area – from the watershed of the Great Divide, through the coastal strip and across the waters of what is called the ‘lagoon’ to the edge of the continental shelf – must be understood and managed with a recognition of the high levels of connectivity within what is in effect a single ecosystem, if optimum environmental balance and sustainable resource yields are to be maintained. Activities in the rainforests, on coastal farmlands, in urban developments, in factories and industrial complexes on the foreshores of harbours and bays all exercise a direct, mutually reinforcing impact – literally, from ‘Divide to Drop-off’.