Although libraries are public spaces in which individuals engage in a range of social and informational activities, few researchers in library and information science use ethnographic approaches to study users' experiences in these settings. This article describes spatial analysis techniques used by geographers and other researchers of social space. It examines the ways in which these techniques may be used to map the physical layout of libraries and information centers, and patrons' uses of those spaces. The article focuses on one observational approach (the 'seating sweeps' method) used to study individuals' use of central public libraries in two large Canadian cities. In addition to a description of the design and implementation of the method, the article presents some of the study's findings that support the utility of this method for facilities redesign or planning to accommodate patrons' information behaviors and usage patterns and to emphasize the central library as a vibrant and vital public space.