Arthrocentesis is a procedure performed to collect synovial fluid from joint spaces for the identification of a disease process or the relief of painful or bothersome symptoms. There are numerous indications for joint fluid aspiration, the most important of which includes the evaluation of synovial fluid for evidence of infection or inflammation. While the procedure specifics vary depending on the joint being aspirated, the general technique and steps remain consistent. The procedure tends to be very safe overall with few complications if performed correctly, and only a small number of contraindications exist.