RICHARD HILL worked for twenty years in design and proposals in the contracting industry and served as marketing director for a specialist process plant contractor. He now runs his own independent consultancy and lectures at Cranfield University, University College London, and UNESCO-IHE in Delft, Holland. GEORGE SOLT spent thirty years in industrial research and development serving as technical director in two-specialist process plant contracting companies before becoming a full-time academic at Cranfield University and University College London.