Despite recent advances in staging modalities, nearly 30-40% of patients undergoing radical prostatectomy for clinically localized prostate cancer have residual disease. In these cases, one or more of the following conditions may be present: extracapsular disease, positive margins, invasion of the seminal vesicles, lymph node metastases or the postoperative persistence of PSA values above the biological threshold. The optimal management for residual prostate cancer remains controversial and in this setting adjuvant therapy could be appropriate. In the present review we examine the conditions in which hormonal adjuvant therapy can be indicated and the results available from retrospective or non-randomized studies. From the data in the literature and in the absence of randomized prospective studies, prudent conclusions could be drawn on the efficacy of adjuvant hormonal therapy. In cases of small volume, low grade (Gleason score < 7) prostate cancer in stage C or D1, radical surgery coupled with adjuvant hormonal therapy leads to survival rates in stage C similar to those in the intraprostatic stage, and in stage D1 with minimal lymph involvement, seems to delay clinical development of metastases. Finally, the quality of life associated with adjuvant therapy and the drug regimens available for this therapy are reviewed.