The Prostate Cancer Prevention Trial is the first phase 3 prevention trial for prostate cancer in the United States. The implementation of a large, randomized trial has provided a wealth of information that will aid in future cancer chemopreventive studies in US men. The experience from the implementation of the Prostate Cancer Prevention Trial was reviewed. Lessons learned from the study include: (1) US men are willing to enroll in prevention trials; (2) participants in chemoprevention trials are well educated and healthy; (3) the successful cancer prevention trial is viewed by participants as a "men's health trial"; (4) data management and discipline coordination at participating institutions are critical; (5) study design change is commonly required owing to changes in clinical practice over the course of the trial; and (6) training of institutional staff is essential. With proper design, robust data management, and a flexible staff, large-scale randomized chemoprevention trials can be accomplished in the United States. With the extraordinary number of potential agents, it is expected that much will be accomplished with this strategy in the near future.