An apparatus is provided for assessing a persons ability to perform tasks requiring hand and eye co-ordination. A gaze tracker 6 images a person's eye in order to determine their direction of look. In the context of a vehicle system, a steering wheel direction sensor 12 is provided to determine the direction of the steering wheel. Data from the steering wheel sensor and the gaze tracker is compared by a data processor 14 which looks for correlations between the data sets and uses this correlation to determine whether the person 2 is fit to drive or not.