Methods: The planned work involves the adaptation/tailoring process followed by a trial with 45 GPs already engaged in collaborative care for adults; the trial will study adding collaborative care for children ages 5-15. GPs will be randomly assigned in groups to begin 6-month control periods involving child mental health screening and referral. They will then receive child/youth training and begin second 6-month periods of screening plus ongoing coaching and booster sessions and collaborative management. Primary outcomes will be measured by recruiting and following for 6 months two cohorts of children/youth and their parents (one control, one collaborative care). Data collected from GPs, parents, youth, and the collaborative care data system will allow measurement of key factors that determine the program's success in helping children and families.