Abstract: A self-propelling and steering attachment for a wheel-chair which can be installed and removed by the user while remaining seated in the wheel-chair and which comprises a sleeve, a steering post rotatably supported by the sleeve, a ground-engaging steering and propelling wheel carried by the lower end of the steering post, a crank mechanism carried by the top end of the steering post, a power transmission connecting the crank and the steering and propelling wheel, a framework which is quickly connectable to, and disconnectable from, the front frame portion of the wheel-chair, and a pair of superposed longitudinally-extending bars interconnecting the framework and the sleeve. The upper bar is rigid with the sleeve at one end and pivots relative to the framework at the other end. The lower bar is pivotally connected to the sleeve and to the framework and is extensible and retractable, being provided with a locking pin to lock this bar to a retracted, adjusted length.