Most patients with B-cell lymphoma face an often incurable disease, particularly those diagnosed with an indolent subtype. The addition of passive immunotherapy to old and new chemotherapy regimens has improved both response rates and disease-free survival, leading in many cases to an extended overall survival. However, a cure remains elusive in most cases. For this reason, the patient- and tumor-specific idiotype, that is the collection of epitopes exclusively presented by the tumor clone’s surface immunoglobulin, has been extensively studied as a privileged target for vaccine therapy, aiming at preventing disease re-occurrence after standard treatment. BiovaxID® (Biovest International, FL, USA), the most clinically advanced among such therapeutic vaccines, finds itself at a crucial turning point when it comes to further development. Both clinical trials in which it has been formally employed have shown intriguing results. Independent studies using slightly different versions of a conceptually identical vaccine provided all proofs of principle required to ascertain the vaccine’s value – biological and clinical efficacy as well as clinical benefit. However, all these data have failed to bring an idiotype vaccine to the market owing to reasons that often have very little to do with the product itself. In fact, some successful studies were not conceived with this goal in mind, while others simply did not enroll enough patients to convincingly make their case for regulatory approval. It is likely that one or more new clinical trials will have to be successfully completed to reach the ultimate goal – that is, to make BiovaxID available to most patients and to adequately position it in the very crowded therapeutic algorithm of B-cell lymphoma.