Argon laser trabeculopuncture was carried out on 7 rhesus monkeys. Perforation of the trabecular meshwork was possible with laser pulses of 100 ms, 4200 mW and a beam diameter of 50 .mu.m. Clinical and histological observations covered an interval of up to 15 wk after coagulation. They revealed an obliteration of both the trabecular holes and the canal of Schlemm after a few days. Shorter pulse durations and higher energies might be helpful to improve the effectiveness, possibly assisted by a therapy with anti-inflammatory agents.