Surgical site infection (SSI) is a major cause of morbidity following elective colorectal resection worldwide. Reduction in SSI rates can be achieved with the use of SSI reduction bundles. Debate about the role of mechanical bowel preparation and oral antibiotics (MOAB) in reducing SSI has persisted over decades with considerable variation in international practice. This article summarises the arguments for and against the routine use of MOAB in the elective setting, highlighting the areas of controversy and evidence gaps and provides pragmatic suggestions for colorectal practice.