This 6-week, partially masked, three-arm, multicenter study was conducted to evaluate the postoperative anti-inflammatory efficacy of ketorolac, a cyclooxygenase inhibitor. The study setting was the clinical practice of six ophthalmic surgeons. The study enrolled 157 candidates for routine extracapsular cataract extraction or phaco-emulsification and posterior-chamber intraocular lens implantation. Patients who received any glucocorticoid or cyclooxygenase inhibitor within 1 week of surgery were excluded. All patients were treated with solutions of 0.5% ketorolac, 1% prednisolone acetate, or 0.1% dexamethasone instilled into the operative eye three times daily from 1 day before surgery to 4 weeks after surgery. Efficacy variables included the signs of anterior-segment inflammation, primarily cells and flare in the anterior chamber, as observed by slit-lamp biomicroscopy; fluorescein leakage across the blood-aqueous barrier as measured by fluorophotometry; and the rating of efficacy by the investigator. No significant differences were seen between ketorolac and either glucocorticoid in cells and flare. No significant differences were found in other signs of inflammation, except conjunctival hyperemia and Descemet's folds at week 2. Ketorolac showed significantly greater efficacy than the glucocorticoids against blood-aqueous barrier breakdown at day 5 and week 2, as demonstrated by the difference in fluorescein concentration between the operated and nonoperated eyes. Investigators did not detect any significant difference in rating for overall effectiveness and acceptability. These findings support the use of ketorolac as an alternative to glucocorticoids for the treatment of postoperative inflammation.