This single arm study will assess the safety and efficacy of MabThera in combination with methotrexate in patients with rheumatoid arthritis who have had an inadequate response or intolerance to one or more anti-TNF agents. Patients will receive MabThera 1000mg i.v. on days 1 and 15, and methotrexate (10-25mg/week p.o. or parenteral), together with methylprednisolone 100mg i.v. prior to infusion of MabThera. The anticipated time on study treatment is 3-12 months, and the target sample size is <100 individuals.