To determine factors which influence postoperative intraocular pressure (IOP) we retrospectively reviewed changes in pressure during the first postoperative week in 633 consecutive eyes undergoing extracapsular cataract extraction (ECCE) with implantation of a posterior chamber lens. The material was restricted to four surgeons and two types of lenses. IOP was measured preoperatively, one day and one week after surgery. Glaucomatous eyes (n = 113) as well as exfoliative non-glaucomatous eyes (n = 79) had a higher mean IOP (27.8 and 26.1 mmHg) the first postoperative day compared to 'simple' cataract eyes (20.1 mmHg). After one week mean IOP in glaucomatous eyes still remained elevated while exfoliative non-glaucomatous eyes had regained preoperative values. Mean IOP on the first postoperative day (18.8, 24.5, 23.1 and 13.2 mmHg respectively) was also dependent on surgeon. To some extent the IOP could be correlated to tightness of suturing as estimated by keratometry. Only one surgeon had significant difference between irrigated and non-irrigated visco-elastic substance. Postoperative pressure was not only dependent on the status of the patient's eye, but factors for the individual surgeons seemed to be as important.