Five hundred and sixty-six patients with either Stage III or IV Hodgkin's disease were prospectively randomized to test whether CCNU and/or vinblastine are more effective than mechlorethamine and/or vincristine with procarbazine and prednisone. The combination of CCNU, vinblastine, procarbazine, and prednisone (CVPP) was shown to be a highly effective program with a complete response frequency of 69%. The use of CCNU as part of the induction program was also shown to be the most significant determinant of prolonged remissions (P = .025). Reduced vomiting and neurotoxicity, as well as the oral administration, were the chief advantages of the CVPP as compared with MOPP. These factors resulted in improved patient and physician compliance. The MVPP regimen was also shown to be a highly effective regimen with a complete response frequency of 73% in patients without prior exposure to chemotherapy. However, the induction regimens containing vinblastine were associated with a significantly higher frequency of fatal hematopoietic toxicities than the induction regimens containing vincristine (P = .05). This higher frequency was almost exclusively seen in the elderly or in patients previously treated with both chemotherapy and radiotherapy. At this time, the remission durations maintained by vinblastine with periodic reinforcement are longer when compared with vinblastine maintenance alone (P = .06), but there is no corresponding increase in survival.