Retail business planning requires detailed consideration of potential security risks, particularly with respect to the crowd- crime relationship. Robbery, extortion, vandalism, and theft in shopping centers and supermarkets must be minimized, and both collective and individual security must be based on prevention and protection. Security planners must have a clear picture of shopping center and supermarket layouts and must identify areas at particular risk. The use of computers and other electronic devices to make shopping centers and supermarkets more secure and crime-free is discussed.