This post-marketing, multi-center, uncontrolled observational study will be conducted in an open-label, non-interventional setting, for RA patients using commercially available adalimumab administered subcutaneously (SC). Adalimumab effectiveness will be assessed based on data from clinic visits beginning at Baseline and continuing per standard of care for RA. The primary objective is to evaluate the effectiveness of adalimumab in improving patients' disease activity measured by Disease Activity Score (DAS28) at Week 12. The maximum observation period for each patient is approximately 52 weeks, as long as the patient continues to receive adalimumab injections. The study was terminated due to low enrollment.