Objectives: Inadequate capacity in Australia’s mental health system means that many people turn to emergency departments (ED) in crisis for care and support, often because it is the only service available. Australian Governments have set a 4-h target for all ED care, but the data shows that people presenting to an ED in a mental health crisis are the group most likely to wait more than 24 h for care. These long waits, seemingly with no end in sight, are harmful for patients and deeply frustrating for clinicians. Conclusions: In response, in 2018, the Australasian College for Emergency Medicine (ACEM) organised the national Mental Health in the Emergency Department Summit. Delegates from across clinical disciplines and user groups were unified in their deep concern at the unacceptable state of mental health support available to people seeking help through EDs. The Summit identified four priorities for urgent action and urged government to take immediate steps to improve this situation.