A steerable wheel assembly comprising a mounting bracket (1) incorporating a vertical pivot mounting (2) for attachment to the vehicle. A second bracket (6) has a first arm (7) carrying a road wheel and a second arm (8) generally upstanding from the first and linked at the upper end thereof to the mounting bracket by a parallelogram linkage (4,5). A spring and shock-absorber unit (9) is pivotally connected between the second bracket and the parallelogram linkage.Another aspect of the invention provides a vehicle suspension system comprising a mounting bracket (20) for attachment to a vehicle body or chassis, and a wheel-mounting arm (21) pivotally attached to the mounting bracket and having a wheel mounted thereon. A spring and shock-absorber unit (22) extends between the mounting bracket and the wheel-mounting arm, at least one end of the spring and shock-absorber unit being connected through a member (23) whose position is adjustable along the axis of the respective bracket or arm.