1985-1986 President, Society of Petrophysicists and Well Log Analysts (SPWLA), Houston, Texas
 1985-1986 Distinguished Lecturer, Society of Petroleum Engineers (SPE),
 2001-2002 Richardson, Texas, USA
 1990-1992 Chair, American Petroleum Institute (API) Working Group on Laboratory Permeability Measurement, Washington, DC, USA
 1991-1994 Member of Council, Geological Society of London, UK
 2001-2003 Chair, Formation Evaluation Committee (SPE)
 2004-2011 Member, Distinguished Lecturer Committee (SPE)
 2005-2006 Reservoirs Coordinator, SPE Programme Committee
 2007-2010 Member, Oil and Gas Reserves Committee and Reserves Education Committee (SPE)



 1987-1990 Special Professor, Department of Geology, University of Nottingham, UK
 1989-1992 Visiting Professor, Department of Geology, University of Leicester, UK
 1990-1997 Senior Visiting Scientist / Research Professor, Lamont-Doherty Earth Observatory / Columbia University, New York, USA
 1997- Visiting Professor, Petroleum Geoscience and Engineering, Imperial College, London, UK



 1982-1988 UK Department of Energy: advisory member of recruitment boards
 1983- Ad-hoc research adviser to governments of Australia, Austria, Canada, United Kingdom and USA
 1986-1992 Chairman, Downhole Measurements Panel, Ocean Drilling Program, Washington, DC, USA
 1991-1994 Member, Earth Sciences Committee, Natural Environment Research Council, UK
 2007- Member, Expert Group on Resource Classification, United Nations Economic Commission for Europe, Geneva