The purpose of this study is to evaluate the difference in relapse rates and long term event free survival in patients with intermediate grade or immunoblastic non-Hodgkin's lymphoma (NHL) whose marrow is not obviously involved with NHL who are randomized to receive either an autologous bone marrow (ABMT) or peripheral stem cell transplant (PSCT). All patients with intermediate grade NHL with histologic negative bone marrow who would otherwise meet all eligibility criteria for high-dose therapy and ABMT are eligible for this study. Patients who are eligible will be randomized to either PSCT or ABMT at the time of enrollment into our transplant program.