We evaluated the effectiveness of using the Potential Acuity Meter (PAM) and automated perimetry to predict postoperative vision in 30 advanced glaucoma patients following combined cataract extraction and trabeculectomy. Using the binomial distribution at alpha = 0.05, PAM and automated perimetry individually were significantly useful in predicting postoperative vision of 20/40 or better. Automated perimetry, but not PAM, was useful in predicting worse than 20/40 vision. Used together, automated perimetry and PAM testing were significantly useful in predicting vision worse or better than 20/40.