BackgroundMajor gaps remain – especially in low- and middle-income countries – in the realization of comprehensive, community-based mental health care. One potentially important yet overlooked opportunity for accelerating mental health reform lies within emergency situations, such as armed conflicts or natural disasters. Despite their adverse impacts on affected populations’ mental health and well being, emergencies also draw attention and resources to these issues and provide openings for mental health service development.Case descriptionCases were considered if they represented a low- or middle-income country or territory affected by an emergency, were initiated between 2000 and 2010, succeeded in making changes to the mental health system, and were able to be documented by an expert involved directly with the case. Based on these criteria, 10 case examples from diverse emergency-affected settings were included: Afghanistan, Burundi, Indonesia (Aceh Province), Iraq, Jordan, Kosovo, occupied Palestinian territory, Somalia, Sri Lanka, and Timor-Leste.Discussion and evaluationThese cases demonstrate generally that emergency contexts can be tapped to make substantial and sustainable improvements in mental health systems. From these experiences, 10 common lessons learnt were identified on how to make this happen. These lessons include the importance of adopting a longer-term perspective for mental health reform from the outset, and focusing on system-wide reform that addresses both new-onset and pre-existing mental disorders.ConclusionsGlobal progress in mental health care would happen more quickly if, in every crisis, strategic efforts were made to convert short-term interest in mental health problems into momentum for mental health reform.