thoughtful analysis reveals that healthcare organizations are considerably more than mere businesses. Peter Drucker (1993) tells us that healthcare organizations are the most complex form of human organization we have ever attempted to manage. This complexity derives from, among other things, the confluence of professions (e.g., physicians, nurses, pharmacists and administrators) and other stakeholders (e.g., patients and government) often with seemingly incompatible interests, perspectives and time horizons. Exacerbating the challenges for healthcare leaders is the well-known need to satisfy what appears to be the insatiable demand for healthcare - without unlimited financial support. With these challenges in mind, this article attempts to lay out a research-based model of how to lead change in healthcare organizations. It uses the implementation of a CPOE system - specifically, Medication Order Entry/Medication Administration Record (MOE/MAR) at Toronto's University Health Network (UHN) - as an ongoing case. In addition to the UHN case, which was largely successful but not without some bumps along the road, additional evidence is drawn from the vast literature on change management. 1 Though this article will use the change at UHN for illustrative purposes, its intended audience includes all healthcare managers, from the most junior to the most senior, in search of a systematic approach to creating order during complex change. Medication Order Entry/Medication Administration Record MOE/MAR is UHN's major patient safety initiative, enabled by computerized medication order entry and medication administration. By supporting clinical decision-making that is consistent with hospital policy and evidence-based practice, MOE/ MAR is intended to