The interest in pair programming (PP) has increased recently, e.g. by the popularization of agile software development. However, many practicalities of PP are poorly understood. We present experiences of using PP extensively in an industrial project. The fact that the team had a limited number of high-end workstations forced it in a positive way to quick deployment and rigorous use of PP. The developers liked PP and learned it easily. Initially, the pairs were not rotated frequently but adopting daily, random rotation improved the situation. Frequent rotation seemed to improve knowledge transfer. The driver/navigator roles were switched seldom, but still the partners communicated actively. The navigator rarely spotted defects during coding, but the released code contained almost no defects. Test-driven development and design in pairs possibly decreased defects. The developers considered that PP improved quality and knowledge transfer, and was better suited for complex tasks than for easy tasks.