Method of and apparatus for steering a vehicle having two separately steerable wheels and respective separate steering means characterized by imparting a steer signal to both steerable wheels, comparing the relative degrees of steer of the respective wheels by way of an ellipsoidal programmer and modifying the steer signal to the steerable wheel that departs from its correct relative degrees of steer with respect to the other steerable wheel. The relative degrees of steer are defined by the ellipsoidal programmer. The ellipsoidal programmer employs the equivalent of two identical ellipses that are placed tangential such that their focal points on their major axes form the apices of a rectangle at the position equivalent to zero degrees of steer, are mounted on pivotal shafts located at opposite first focal points and have their other respective and opposite focal points free to move in a plane as the driving ellipse drivingly rotates the driven ellipse through a connection that is equivalent to being retained tangential. The driving ellipse is rotated twice the number of degrees a first steerable wheel is being steered, and the output from the driven ellipse can be compared directly with twice the degrees of steer of the other steerable wheel. A preferred embodiment in which the modifying of the steer signal comprises interrupting the steering signal to the steerable wheel that is being steered more than its correct relative degrees of steer with respect to the other steerable wheel, and specific apparatus are also disclosed.