Youth engagement can improve the accessibility, effectiveness, and sustainability of programs and resources for youth. Little is known about youth engagement in system-level initiatives. As part of Systems Improvement through Service Collaboratives, an Ontario initiative that aimed to improve the system of care for youth with mental health or addictions needs, youth and adults in London, Ontario partnered to co-create Be Safe. The Be Safe resource helps youth manage mental health crises and identify local services. This article showcases a youth-adult partnership in a system-level initiative, and highlights a replicable strategy for developing resources relevant to youth needs and preferences.