A transmission for a walk-behind wheeled vehicle, the transmission being of the type including at least one casing (2) housing a driver member (3), equipped with rotary 
drive motor means (4), a rotary driven member (5), 
two wheel drive shafts (6A, 6B) in alignment, two 
clutch mechanisms (8) each of which is disposed between the driven member (5) and a 
wheel drive shaft (6A; 6B), each 
clutch mechanism (8) being activated by the driven member (5) being driven in rotation forwards, and deactivatable by the 
wheel drive shaft (6A; 6B) with which it co-operates being driven in rotation forwards, when the speed of rotation of the 
wheel drive shaft (6A, 6B) is greater than the speed of rotation of the driven member (5). The rotary 
drive motor means (4) for driving the driver member (3) in rotation are motor means that can be controlled to rotate in two directions of rotation, and each 
clutch mechanism (8) is of the type that is deactivatable merely by the driven member (5) being driven in rotation in the backwards direction.