Medical physicists make a major contribution to the safe and effective radiation treatment of patients with cancer. Academic education as well as clinical training is required prior to being able to practise radiation oncology medical physics. However, in particular in developing countries the problem frequently exists that resources with respect to both, qualified teachers and equipment, that is at disposal for teaching and training, are lacking. Concepts of e-learning may contribute to overcome this problem. Whereas e-learning material is more and more available for academic teaching, modules for clinical training are still rare. This has motivated us to develop a virtual training module for the calibration of high energy photon and electron beams. A PC based program simulates the required equipment, the measurement set-up, and the measurement itself; it also serves as a guide through the evaluation of the virtually measured data. All procedures are modeled according to the IAEA Code of Practice, TRS 398.