In this issue Ibrahim and co-authors report on technical hazards of off-pump (without heart lung machine) coronary surgery 1. Their findings are in line with meta-analyses of randomized trials which indicate that under-grafting and graft-failures are more common after off-pump than after standard operations. The risk that the objectives of coronary bypass surgery are endangered is discussed in relation to evidence based medicine. A moratorium is suggested until conclusive data are available.