Youth with substance use disorder frequently have co-occurring psychiatric symptoms/diagnoses. Moreover, children and adolescents with mental health symptoms are highly vulnerable to initiating substance use, including non-medical use of prescription opioids. This webinar is aimed at general pediatricians and pediatric sub-specialists but any parent, teacher or concerned adult will find this resource useful. First, a review of current clinical information about the prevalence of psychiatric illness and substance use disorder is provided followed by an overview of clinical tools to aid in recognizing symptoms of common psychiatric illness. Trends in adolescent substance use change quickly but primary care providers are most likely to encounter issues related to tobacco, alcohol and cannabis. A demonstration of sample approaches to substance use screening with a focus on detecting risk in settings where opioids may be prescribed is also offered. This clinical issue is a complex one as differentiating which came first (substance use disorder or mental health condition) is not always obvious, especially in the face of contemporary psychosocial issues in adolescents.