This report describes the outcome of the Specialist Meeting of the NCGIA Research Initiative 21 on "Formal Models of Commonsense Geographic Worlds". The meeting was held in San Marcos, TX on October 30- November 3, 1996.

Research Initiative 21 is concerned with the development of formal models of commonsense geographic worlds. Discussions at the Specialist Meeting focused on the commonsense or naive geographic reasoning that people perform and whose outcome makes intuitive sense to most people. The Specialist Meeting brought together specialists from geographic information science, artificial intelligence, computer science, geography, developmental psychology, and behavioral science to foster discussions leading towards a better understanding of the nature of naive geographic reasoning and how better to incorporate naive geographic knowledge and reasoning into GIS.

This Report serves to document the discussions held during the meeting and, most importantly, delivers a set of researchable questions that forms the basis for future research in this area. Participants collected close to 50 questions worthy of further consideration and research on topics relating to the fundamentals of Naive Geography, developmental influences on Naive Geography, and the impact of Naive Geography on GIS.