Despite its advantages in diagnosis, treatment and research, the role of arthroscopy in the management of rheumatic diseases has diminished due to the development of other less invasive means of joint assessment including advances in imaging techniques, e.g. ultrasound and magnetic resonance imaging. However, arthroscopy still provides invaluable information. By direct and precise internal inspection of a joint, arthroscopy allows the collection of synovial membrane samples (biopsies) of excellent quality, notably from the most representative pathological areas. Arthroscopy may also play a therapeutic role in the management of inflammatory arthritis (IA) by providing pain relief (lavage). Here we describe the procedure of knee arthroscopy under local anaesthesia, as well as an in situ visual assessment of synovial inflammation and its correlation with degree of histological and immunological abnormalities. With the emphasis being placed on early diagnosis and treatment initiation in patients with IA and as earlier initiation of targeted biologic therapies becomes more commonplace, the ability to predict which patients will respond to the different therapies available would be invaluable. Assessment of arthroscopic derived synovial biopsies has potential to play an important role in management of early IA in the future.