A new system, Physilog, for ambulatory monitoring of movement is proposed and its applications in orthopaedic, physiology, angiology and quality of life are presented. Body accelerations were recorded by a portable measuring device. Significant parameters of body motion, namely, movement coordination, temporal parameters, speed, incline, distance covered, kind of physical activity and its duration, are extracted from the subject accelerations in its daily environment. The accuracy of these parameters guarantees the reliability of accelerometry in clinical application.