Radiolabelled immunotherapy is a significant step forward in the treatment of non-Hodgkin's lymphoma (NHL), with preliminary data suggesting long remissions in some patients. 90Y-ibritumomab tiuxetan is the only therapy approved for use after rituximab failure and is currently indicated in the EU for the treatment of adults with rituximab-relapsed or refractory CD20-positive follicular B-cell NHL. However, retrospective analyses confirm better responses when 90Y-ibritumomab tiuxetan is used earlier in the disease course. An expert panel of oncologists, haematologists and nuclear medicine physicians met at an European workshop to discuss proposed therapeutic algorithms for follicular lymphoma and the preliminary medical evidence supporting the incorporation of 90Y-ibritumomab tiuxetan as an early therapeutic option. Phase II data indicate that 90Y-ibritumomab tiuxetan either alone as primary therapy or as consolidation therapy following induction chemotherapy with or without rituximab achieves high response rates in follicular lymphoma, with complete remission rates of 62-80%. Phase III data are warranted, but based on preliminary observations the expert panel recommended incorporation of radiolabelled immunotherapy into national lymphoma treatment algorithms across Europe. This approach would maximise the therapeutic potential of this agent by encouraging its use early in the disease course of follicular lymphomas.