This investigation sought answers to three main questions 1. Irrespective of level of performance in undergraduate anatomy, descriptive astronomy or engineering drawing, do students with poor spatial visualization ability significantly under-achieve in university class examinations in these subjects relative to their spatially competent peers? If this is the case: 2. Can a battery of spatial exercises be employed to diagnose severe three-dimensional impairment amongst students failing in anatomy, descriptive astronomy and engineering drawing and, if so, what is the optimum composition of such a battery? 3. For the purposes of counselling and possible remedial teaching, at which stage during a course of university study should failing students be tested for suspected spatial ineptitude? The investigation from 1980 to 1983 involved four populations of anatomy students, three populations of astronomy students, one year of engineering students and one group of clinical remedial mathematics students. The academic performances of 1126 students were monitored during this period, and 621 of these students were singled out for special measurement of spatial achievement in their academic subjects.