Essential drugs policy in three rural counties in China: What does a complexity lens add?

► The implementation of the essential drug policy in China is understood as a complex, nonlinear and dynamic process. ► Interviews with key stakeholders revealed unanticipated adaptive behaviors and produced a variety of unpredicted outcomes. ► Using insights from complex adaptive systems can inform policy making. ► Post-implementation monitoring of the different behaviors of key actors can help to respond quickly to the unintended consequences.