A steering column assembly comprises an adjustable shroud which at least partially surrounds a steering shaft and a clamp mechanism operable between a clamped position in which the adjustable shroud part is locked in position and an unclamped position in which the adjustable shroud part can be moved to set the reach and/or rake of the steering column assembly, in which the clamp mechanism comprises a clamp pin, a locking handle and a cam mechanism fitted to the clamp pin, in which the cam mechanism comprises first and second cam portions which can be moved relative to each other by operation of the locking handle to vary the overall length of the cam mechanism, the unclamped position of the cam mechanism being defined by contact of a first end stop of the first cam portion with a second end stop of the second cam portion. At least one of the end stops comprises a resilient cushioning element which provides cushioning as the at least one end stop engages the other end stop upon the clamp mechanism reaching the unclamped position.