In spite of their tragic nature, and notwithstanding the human suffering they create, emergency situations are also opportunities to build better mental health care. The surge of aid, combined with sudden, focused attention on the mental health of the population, creates unparalleled opportunities to transform mental health care for the long term.By publishing this information, the World Health Organization aims to ensure that those faced with emergencies do not miss the opportunity for mental health reform. Emergencies are not only mental health tragedies, but also powerful catalysts for achieving sustainable mental health care in affected communities. We do not know where the next major emergency will be, but we do know that those affected will have the opportunity to build back better. Reading this publication is an excellent way to prepare for and respond to that eventuality. The ten cases that form the core of this report show how it can be done. Early commitment towards a longer-term perspective for mental health reform is key to success. The report summarises lessons learnt and key overlapping practices emerging from these experiences.