The risk factors for intraoperative and early postoperative complications were evaluated in 351 consecutive cataract operations at the Oulu University Hospital in 1990. Bleeding into the anterior chamber during the operation was recorded in 8.6%, zonular rupture in 6.6%, posterior capsular rupture in 5.4% and vitreous loss in 3.2%, On account of the loss of capsular support an anterior chamber intraocular lens was implanted in 3.1%. Of the early postoperative complications, signs of fibrinous reaction were observed in 24.5%, corneal edema in 53.6% and rise of intraocular pressure to 30 mmHg or more in 27.6%. There was no difference in the complication rate between men and women or in relation to age. The use of anticoagulant (although discontinued before surgery) or antiplatelet medication increased the risk of intraoperative bleeding but no sight-threatening bleeding occurred. The use of acetylsalicylic acid was also associated with an increased risk of postoperative fibrinous reaction. Other systemic diseases like systemic hypertension, diabetes, asthma, or cardiac or mental disorders, or medications, did not increase the complication rate. Of the various ocular parameters, small pupil and exfoliation syndrome were the most important risk factors for both intra- and early postoperative complications, and the presence of glaucoma increased the risk of vitreous loss, postoperative pressure rise and corneal edema. General anesthesia did not seem to reduce the complications rate.