If you have been diagnosed with rheumatoid arthritis (RA), you are not alone. Approximately 1.5 million Americans have RA, an autoimmune disease that causes inflammation, pain, and damage to the joints. In RA, the immune system attacks the body’s own tissues, specifically the thin membrane surrounding the joints called the synovium. If untreated or under treated, this inflammation will lead to worsening RA symptoms and joint damage over time. Joint damage can begin as early as 3 months after the onset of RA symptoms in some people. It is important to work closely with your doctor and discuss your symptoms and treatment options frequently. The information in this “Patient Toolkit” is designed to help you understand RA so that you can fully participate in treatment decisions. In this toolkit, you will find answers to frequently asked questions, advice and tips on living with RA, and links to additional resources.