Commissioning a linear accelerator for clinical use poses great challenges to a medical physicist as the quality of the beam data acquired may affect the radiation outcome. This two-day training course covers all major aspects of LINAC commissioning in theory and practice. It aims to provide participants with a fundamental knowledge of the physics, procedures and techniques required for beam data acquisition for the treatment planning system. Particular emphasis is placed on the proper and efficient use of the appropriate dosimetry equipment, setup issues, typical problems encountered during the commissioning phase as well as relative dose measurements in small fields. The training course is held in a well-equipped dedicated university hospital by experienced professionals, offering attendees an ideal environment for practicing the various LINAC commissioning measurements. With its mix of lectures, case studies and hands-on sessions, it primarily targets medical physicists with no or little experience in the commissioning of medical linear accelerators who want to acquire the necessary knowledge and techniques in a relaxed and informal atmosphere.