Athletes commonly experience mental health symptoms. However, prevalence estimates require refinement so that symptoms are interpreted in context and diagnostic labels are accurately applied. Further prevalence studies are also needed in subgroups within sport, in particular female athletes, athletes with disabilities, and coaches. Existing consensus-based and evidence-based therapies must be adapted not only to the individual athlete but also to the ecology of sports. Filling the gaps in our knowledge on what treatment modifications may be required for the individual athlete and how services should be designed to deliver treatment most effectively will require well-designed studies that use standardized terminology and defined outcome measures.