This article examines information source selection behavior among maintenance technicians and how this behavior might influence the design of technical information. For this entry, "maintenance technicians" are individuals who maintain machine equipment (e.g., generators or bearings) in industrial enterprises, and this process includes the troubleshooting of problems and the repairing of machine equipment. In this entry, the authors use a review of the literature on information source selection behavior to discuss core concepts within the field of source selection behavior. Three of the main concepts examined are "information," "information source," and "source preference criteria." These core concepts function as a frame of reference for discussing how maintenance technicians might select information sources to perform maintenance activities. The authors also use these concepts to review why certain sources are selected for use over others. The results tentatively suggest maintenance technicians prefer information sources that can be adapted to specific workplace contexts.