OBJECTIVE: Many patients with an inguinal hernia are asymptomatic or have little in the way of symptoms from their hernia. Repair is often associated with long-term chronic pain and has a recurrence rate of 5% to 10%. Our aim was to compare operation with a wait-and-see policy in patients with an asymptomatic hernia. METHODS: A total of 160 male patients 55 years or older were randomly assigned to observation or operation. Patients were assessed clinically and sent questionnaires at 6 months and 1 year. The primary endpoint was pain and general health status at 12 months; other outcome measures included costs to the health service and the rate of operation for a new symptom or complication. RESULTS: At 12 months, there were no significant differences between the randomized groups of observation or operation, in visual analogue pain scores at rest, 3.7 mm versus 5.2 mm (mean difference, -1.6; 95% confidence interval (CI), -4.8 to 1.6, P = 0.34), or on moving, 7.6 mm versus 5.7 mm (mean difference, -1.9; 95% CI, -6.1 to 2.4, P = 0.39). Also, the number of patients 29 versus 24 (difference in proportion, 8%; 95% CI, -7% to 23%, P = 0.31), who recorded pain on moving and the number taking regular analgesia, 9 versus 17 (difference in proportion, -10%; 95% CI, -21% to 2%, P = 0.14) was similar. At 6 months, there were significant improvements in most of the dimensions of the SF-36 for the operation group, while at 12 months although the trend remained the same the differences were only significant for change in health (mean difference, 7.3; 95% CI, 0.4 to 14.3, P = 0.039). The rate of crossover from observation to operation 23 patients at a median follow-up of 574 days was higher than predicted. The observation group also suffered 3 serious hernia-related adverse events compared with none in the operation group. CONCLUSIONS: Repair of an asymptomatic inguinal hernia does not affect the rate of long-term chronic pain and may be beneficial to patients in improving overall health and reducing potentially serious morbidity.