We performed a prospective study of relaxing incisions with augmentation sutures in 21 patients who were unable to wear spectacles or contact lenses after penetrating keratoplasty because of high astigmatism. The mean preoperative astigmatism was 9.37 diopters (range, 4.50 to 14.50 diopters), and the mean postoperative astigmatism was 3.73 diopters (range, 0.00 to 7.00 diopters). The net decrease in astigmatism was 6.56 diopters (range, 1.00 to 11.00 diopters), which represents a 67% decrease in astigmatism. The mean vector corrected change in astigmatism was 8.40 diopters (86%). These results were compared with those of our previous study of relaxing incisions without sutures. Overall, there was a significantly greater decrease in astigmatism (67% vs 47%, P = .009) when augmentation sutures were placed 90 degrees away from the relaxing incisions. Furthermore, in patients with more than 8.50 diopters of astigmatism, relaxing incisions with sutures yielded a much greater reduction in astigmatism compared with relaxing incisions without sutures (70% with sutures vs 39% without sutures, P = .002). We recommend relaxing incisions with augmentation sutures as the initial surgical procedure in eyes with more than 8.50 diopters of astigmatism.