The purpose of this study is to estimate the retention rate of Abatacept over 24 months in routine clinical practice in every participating country depending on the treatment line.

Time Perspective: Other: Collection of the baseline data collected at Abatacept IV initiation, prospectively or retrospectively within maximum 3 months following the first administration. Other assessments are collected during the follow up period (maximum of 2 years by patient)

Biospecimen Retention: None Retained excepted for a local sub study (in Spain) where sample with DNA was retained

For more information regarding BMS clinical trial participation, please visit www.BMSStudyConnect.com

Inclusion Criteria:

• Male or Female subjects of more than 18 years old
• Patients with a diagnosis of established moderate to severe active RA (as per the American College of Rheumatology revised criteria, 1987), who at their physician's discretion are treated with Abatacept according to the SmPC in Europe and the Product Monograph in Canada (initiating or already on treatment for maximum 3 months) and for whom baseline characteristics are available

Exclusion Criteria:

• Patients who are currently included in any interventional clinical trial in RA

Crohn's Disease