Thirty-eight eyes were treated by adding timolol to the medical regimen. After a suitable trial, attempts were made to reduce other glaucoma medications. Fifteen eyes with infantile glaucoma treated surgically at birth, experienced elevated intraocular pressure later in life. Another 15 eyes had glaucoma associated with congenital anomalies such as aniridia, Sturge-Weber syndrome, and mesodermal malformations. The group with infantile glaucoma demonstrated an average drop in pressure of 24% and 22% after one and three months, respectively. Six of the 15 eyes were controlled at 22 mm Hg or less. In the other group, intraocular pressure fell 30% after one month and 12% after three months. Five of the 15 eyes were controlled. Adverse effects occurred in five patients, timolol therapy was discontinued in two (7%). The IOP was not controlled in any of the eyes with timolol alone.