An exercise and gait-training apparatus (1) is disclosed for use in the rehabilitation of disabled persons but is also suitable for use by sportspersons who wish to correct or alter their gait to improve their performance. The apparatus comprises a framework (2) adapted for location above a surface. A harness (15) is provided to support a person relative to the framework (2) and an orthosis (23) is also provided for attachment to a lower leg or foot of the person. A first pair of first actuators (14a, 14b) is adapted to move one side of the harness (15) and a second pair of first actuators (26a, 26b) adapted to move the orthosis (23) relative to the framework (2). A control means (6) is provided to control and to synchronize operation of the actuators (14a, 14b, 26a, 26b) so that the first leg is moved in a pathway simulating a natural movement of the leg during a walking, a running or a sporting activity. Preferably a second orthosis (23) is provided for attachment to the other leg. Both static and mobile embodiments of the apparatus (1A, 1B) are possible, in the latter case the framework (2) is provided with wheels (3, 4).