Professor Yeh’s research has centred on the use of GIS and spatial analytical methods in urban planning and development. His work has addressed the integration of GIS with case-based reasoning, cellular-automata models incorporating environmental and urban-form variables, and spatial analysis of employment and residential location in Hong Kong. He has also examined the social and spatial structure of Chinese cities, the relationship between land-property rights and urban development, and the transformation of the Pearl River Delta, contributing to research on regional development and spatial restructuring in southern China. His research has received the UN-HABITAT Lecture Award, the Dr. Gill-Chin Lim Global Award of the Association of Collegiate Schools of Planning, the Distinguished Research Achievement Award of the University of Hong Kong, and the Lifetime Achievement Award in GIS of the International Association of Chinese Professionals in Geographic Information Sciences. He has published more than 30 books and monographs and over 180 international journal papers and book chapters, and has served on the editorial boards of journals including Computers, Environment and Urban Systems, Transactions in GIS, and Progress in Planning. He has also contributed to public planning and transport policy through service on advisory and statutory bodies of the Hong Kong SAR Government. Through sustained research in GIS-based planning, academic institution building, and the training of younger scholars, Professor Yeh has contributed to connecting spatial information science with urban and regional planning practice and to the development of urban studies and geographic information science in Asia.