ABSTRACT. This paper provides an overview of quantitative geography. In addition to discussing what quantitative geography is, the paper details the methods that have come to define it. Six broad categories are used to discuss the range of methods found in quantitative geography: geographic information systems; airborne sensing (global positioning system, photogrammetry, and remote sensing); statistics and exploratory spatial data analysis; mathematics and optimization; regional analysis; and computer science and simulation. Particular emphasis is given to the state of the art in each area and the contributions of geographers, with associated discussion on major unresolved issues and future research directions.