A marine ecologist, he studied crown of thorns starfish and large scale surveys of the Great Barrier Reef and was a foundation member of the planning and research staff of the Great Barrier Reef Marine Park Authority in 1977, retiring in 1999 as Executive Director of the Authority.
He is currently a professor at the Australian National Centre for Ocean Resources and Security of the University of Wollongong, Australia. Current research includes synthesis of a trans disciplinary CSIRO Coastal Cluster project concerning barriers to the application of science in coastal zone management for climate change.
He works widely as a consultant and advisor to governments and international agencies. In 2009 he was appointed as external advisor for Marine Studies, University of the South Pacific. He is currently working as a member of a panel inquiring into port management in the Great Barrier Reef World Heritage Area and for the United Nations Environment Programme (UNEP), on the implementation regional marine and coastal strategies for management of coral reefs and associated ecosystems.
He has published widely management of coral reef, coastal and marine. Books include Managing Marine Environments (1990, Taylor and Francis) and Sustainable Coastal management and Climate Adaptation (2012, CSIRO Press).