Monoclonal antibodies are an exciting advance in the treatment of lymphoma. They are safe and well-tolerated, and exhibit little cross-resistance with conventional chemotherapeutic agents. In indolent lymphomas, antibody therapy has shown useful response rates, both as first-line therapy and in relapsed disease. Follicular lymphomas appear to be particularly sensitive to rituximab, and chronic lymphocytic leukaemia to alemtuzumab. In aggressive lymphomas, the addition of rituximab to CHOP chemotherapy significantly lengthens disease-free and overall survival compared to CHOP alone as first-line therapy. Newer agents, including radiolabelled antibodies, immunotoxin-linked antibodies and antibodies against novel target antigens are showing promise in phase I and II trials in a variety of clinical settings.