Gikas Mageras has become Chief of the Computer Service in the Department of Medical Physics. As Chief of the Computer Service, Dr. Mageras coordinates the activities of a team of medical physicists, programmer/analysts, and computer management staff in developing and supporting advanced computer applications that serve the departments of Medical Physics, Radiation Oncology, and Radiology. A major portion of the team's activities is devoted to development of computer systems for external radiotherapy and brachytherapy treatment planning. Dr. Mageras's own research interests have focused on improving the accuracy of radiation therapy by developing new patient imaging and treatment techniques to locate tumors more precisely and to reduce the movement of internal organs during treatment. Dr. Mageras received his PhD degree in physics in 1983 from Columbia University. Prior to his career change to medical physics, he was a research scientist in experimental particle physics at the Max Planck Institute for Physics and Astrophysics in Munich, Germany. He joined Memorial Sloan-Kettering in 1988.