Gout is one of the most common inflammatory arthritidies in men and postmenopausal women. It causes recurrent and severe pain in the affected joints, especially in the first metatarsophalangeal joint. The stages of gout are divided into asymptomatic hyperuricemia, acute intermittent arthritis with intercritical period and chronic tophaceous gout. It also affects kidney and causes nephrolithiasis and urate nephropathy. Gout can be diagnosed by confirming monosodium urate crystals in the joint fluid through polarizing microscope. In some cases, clinical diagnosis can be made based on the typical features of the attacks. Differential diagnosis from infectious arthritis is important. (Korean J Med 2011;80:255-259)