A pedestrian truck (50) steered with a tiller (56) is operable in a first mode where a controllable front wheel (64) is aligned generally parallel with a front-rear centre line of the truck, or a second mode where the wheel is generally perpendicular to the front-rear centre line. A steering controller can operate in either a normal steering mode to steer the rear steerable wheel (52) in the same sense (clockwise or anticlockwise) as the tiller is rotated and in an alternate steering mode to steer the rear steerable wheel in the opposite sense to the rotation of the tiller. A steering mode selector is provided which automatically engages the alternate steering mode when the truck is in the second mode of operation and either (i) the tiller is positioned on the same side of the centre line as the controllable front wheel and the drive direction is such that the tiller leads the truck (FIGS. 12-14), or (ii) the tiller is positioned on the same side of the centre line as the castor front wheel (58) and the drive
