Prostate cancer incidence and mortality trends in the United States continue to perplex researchers. The rise and subsequent decline in prostate cancer incidence can clearly be traced to the introduction of prostate-specific antigen testing. However, prostate cancer mortality rates have fallen sooner and faster than can be attributed to the impact of surgery and radiotherapy. Computer modeling by the National Cancer Institute's Cancer Intervention and Surveillance Modeling Network (CISNET) research teams provides insights into these complex relationships.