Chronic subdural hematomas in adults are not technically difficult to treat. They probably constitute one of the most common potentially curable lesions with which the average neurosurgeon deals. Despite this (or perhaps because of it) numerous treatments, radically differing from one another, have been advocated. Fine judgment is called for in deciding whether or not to operate in the first instance, make a flap or one or more burr or twist drill holes, use a drain, employ suction, inflate the brain, leave the bone flap out. In a personal series of 71 chronic subdural hematomas, 46 were treated with a red rubber catheter drain through a burr hole and 23 with a closed system suction drain. The results of this series suggest that closed system suction drainage through a single burr hole is the better of the two techniques. It has important theoretical advantages and the procedure is simple and fast. The complication rate is low and patients have a shortened postoperative hospital stay.