Social workers play a critical role in assessing and treating individuals and families with mental health and addiction concerns. Although social workers are key professionals in the mental health workforce, there are gaps in the training and education of mental health, addictions, and suicide, and many students are inadequately prepared for field education. Simulation-based learning is an exemplar method of teaching and assessing practice competencies across several health-care professions including social work. This teaching note describes a simulation-based learning activity in which MSW students build competence in mental health, substance use, and suicide risk assessments with standardized clients. This innovation is integrated in a social work practice in mental health course and was developed in partnership with a community mental health and addiction treatment center. Through this partnership, we developed core competencies, case scenarios, as well as teaching resources and assessment instruments. An advisory committee consisting of MSW students, faculty members, and field instructors evaluated the simulation-based learning innovation and made recommendations for the next iteration. Implications for teaching social work practice in mental health are discussed.