There is a significant deficit in the evaluation of mental health services for children and youth worldwide. Such evaluation in children has been more complicated than parallel efforts to assess general health services and mental health services for adults. For instance, the Triple Aim of the Institute for Healthcare Improvement (IHI), widely used in evaluating health care in general, focuses on health outcomes, patient experience, and costs per member per year. But in child mental health, outcomes must be assessed over time, addressing developmental resilience, not just in the moment; the experience of parents must be assessed along with those of children; and relevant costs are dispersed (and must be measured) across the domains of healthcare, mental health services, education, and child welfare. In this presentation we will discuss such difficulties in evaluation and how mental health should be measured, present data from the WHO Atlas Projects (including the global atlas as well as the Eastern Mediterranean Atlas), and discuss shortcomings and evidence gaps from these atlases.