Abstract: A steering system for use in a towing vehicle-steering trailer assembly, wherein all trailer axles are load-bearing and fixed. The steerable trailer includes a sectored radian steering mechanism which comprises a sectored rack-and-pinion mechanism keyed to the towing vehicle fifth wheel plate. The sectored rack-and-pinion mechanism provides a steering output signal proportional to the relative angle between the towing vehicle and the steerable trailer which approaches an asymptote and thus allows the towing vehicle to turn in relation to the steered trailer without generating the steering mechanism output signal.