Editorial Perspective: Adverse childhood events causally contribute to mental illness - we must act now and intervene early.

We synthesized critical evidence regarding causal inferences of Adverse Childhood Experience (ACE) exposure and subsequent disease development. Extensive and high-quality research supports causal inferencing and offers a solid ground for policy- and decision-makers interested in translating science into societal action. There is ample evidence supporting system-wide implementation of prevention and treatment even though research on mechanisms needs to and will continue to offer additional insights.