PURPOSE: Watchful waiting (WW) is an acceptable strategy for managing prostate cancer (PC) in older men. Prostate-specific antigen (PSA) testing has resulted in a stage migration, with diagnoses made in younger men. An analysis of the Department of Defense Center for Prostate Disease Research Database was undertaken to document younger men with low- or intermediate-grade PC who initially chose WW. PATIENTS AND METHODS: We identified men choosing WW who were diagnosed between January 1991 and January 2002, were 70 years or younger, had a Gleason score < or = 6 with no Gleason pattern 4, had no more than three positive cores on biopsy, and whose clinical stage was < or = T2 and PSA level was < or = 20. We analyzed their likelihood of remaining on WW, the factors associated with secondary treatment, and the influence of comorbidities. RESULTS: Three hundred thirteen men were identified. Median follow-up time was 3.8 years. Median age was 65.4 years (range, 41 to 70 years). Ninety-eight patients remained on WW; 215 proceeded to treatment. A total of 57.3% and 73.2% chose treatment within the first 2 and 4 years, respectively. Median PSA doubling time (DT) was 2.5 years for those who underwent therapy; those remaining on WW had a median DT of 25.8 years. The type of secondary treatment was associated with the number of patient's comorbidities (P =.012). CONCLUSION: Younger patients who choose WW seemed more likely to receive secondary treatment than older patients. PSA DTs often predict the use of secondary treatment. The number of comorbidities a patient has influences the type of secondary therapy chosen. The WW strategy may better be termed temporarily deferred therapy.