This single arm study will evaluate the safety and efficacy of MabThera in participants with active rheumatoid arthritis who have had an inadequate response to prior treatment with DMARDs and/or anti-TNF alpha agent. Participants will be treated with MabThera 1000 milligrams (mg) intravenously (IV) on days 1 and 15. Participants were followed every 8 weeks to complete 24 weeks of follow-up. After completion of the Week 24 visit, the participants were followed every 3 months for up to 18 months for an overall study duration of 24 months (104 weeks). After week 36, eligible participants who achieve moderate or good response according to the European League Against Rheumatism (EULAR) response criteria will receive re-treatment with MabThera. Participants will receive concomitant treatment with DMARDs, corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics throughout the study period. The anticipated time on study treatment is 2 years, and the target sample size is 200 participants.