This review paper explores documented episodes of malaria resurgence worldwide, and assesses their association with malaria control programmes, a higher risk of disease transmission and drug resistance. It identifies 75 instances of resurgence in 61 countries over a period of 70 years, with the vast majority related to weakening control programmes, usually due to limited resources. This suggests that gains in malaria control can be lost rapidly if support is not sustained. The authors argue that finding ways to sustain funding for control programmes is crucial, and that there is an urgent need to develop practical solutions to operational and technical threats to their success.