Abstract: A rear wheel steering system for trailers operative to permit selective steering of the rear of a trailer by swinging a rear wheel and axle assembly relative to a trailer frame and independently of the steering of a towing vehicle. The system includes extensible members each having respective opposite ends thereof pivotally connected to a frame of the trailer and to a mounting member having the rear wheels and axle assemblies mounted thereon and operative to selectively turn the mounting member and wheels and axle assemblies thereon relative to the frame of the trailer for steering of the rear end thereof.