Surgeons are aware of the adverse effect that resection-line disease has on anastomotic leakage, perioperative mortality and long-term survival. In an attempt to assess the effect of this knowledge on surgical practice, patients entered into the second British Stomach Cancer Group adjuvant therapy trial were studied. The presence of resection-line disease was compared with the operative stage. Of 555 patients for whom complete data were available, resection-line disease was present in 105 (19 per cent). Of 424 patients undergoing what the surgeon considered to be a potentially curative operation, 55 (13 per cent) had involvement of one or both resection lines, rendering the surgery palliative. Only 9 per cent of patients with stage I-III disease and resection-line involvement survived beyond 5 years, compared with 27 per cent of those with clear lines. Despite knowledge of the adverse effects of resection-line disease, surgeons continue to perform inadequate resections. This demonstrates the need for a more aggressive approach to assessment of resection margins at operation.