Comparative measurements of intraocular pressure of 200 eyes were statistical analyzed. Goldmann applanation tonometry was performed by the author and was accepted as a reference system for the measurements made by a technician using the Pneumatonograph, the GlaucoTest screening tonometer, the Halberg tonometer and the Schiotz tonometer. The technician was trained in the use of these instruments for two days; The Pneumatonograph results on seated patients were in good agreement with the Goldmann readings. The GlaucoTest screening tonometer proved to be a good screening instrument for ocular hypertensives and required only a short period of training for the technician. The Halberg tonometer did not give precise readings of intraocular pressure, however, it was more difficult for technicians to use. The Sciotz tonometer appeared to be of limited value in screening tonometry. Some aspects of the influence of body position on i.o; pressure in the different tonometric procedures have been discussed.