Medication errors are not random events, nor are they necessarily evidence of a lack of carefulness on the part of the practitioner concerned. To a substantial degree, the particular type of medication error that is likely to occur in a particular set of circumstances is predictable. Furthermore, each of these types of error will continue to occur at their current rate if we continue with current approaches to the management of medications in the perioperative period. Errors will not be reduced by ongoing calls for greater carefulness on behalf of individual practitioners. Instead, the need is for fundamental changes in the ways in which medications are presented, selected and administered to patients. Greater investment in systems-based initiatives to improve medication management is essential if medication safety is to improve. However, it is also essential for clinicians to engage with such initiatives if they are to be effective. Achieving this requires sustained effort by departments and institutions, informed by the principles of implementation science.