This observational study will evaluate the safety, tolerability and efficacy of RoActemra/Actemra (tocilizumab) in combination with methotrexate in patients with moderate to severe rheumatoid arthritis. Data will be collected for 12 months from patients initiated on treatment with RoActemra/Actemra (8 mg/kg intravenously every 4 weeks) and methotrexate (weekly dose at the discretion of the physician).