Professor of Human Geography in the School of Geosciences at the University of Sydney, Australia. He specialises in natural resource management, rural change and the politics of environment in Southeast Asia.

He leads the Mekong Research Group, which carries out engaged and collaborative research on a range of natural resources governance, livelihood and development themes in the Mekong region.

He has been working on and in Thailand, Laos, Vietnam and Cambodia since the eraly 1980s. He is fluent in Thai and Lao, and also speaks and reads passable Vietnamese and some Khmer.

He has written extensively on land, forest, water and fisheries in the Mekong region and is also an area studies specialist on Thailand, Laos, Cambodia, Vietnam and the wider Mekong Region. More specific interests include river basin management, deforestation, environmental impact of development, rural social differentiation and agrarian change, the role of NGOs in development, resource tenure, changing relations between village and state, and community-based natural resource management.

His research work includes projects supported by the Australian Research Council, Australian Centre for International Agricultural Research, Australian Agency for International Development, International Development Research Centre, Australian Water Research Facility, Asia Research Centre and Danish International Development Assistance.