Background Transition from pediatric to adult health care is a pivotal process for young adults, especially those with complex medical needs. Despite advancements in the medical care provided to children with medical complexity (CMC), there is a lack of systematic approaches and guidance for patients and families transitioning from pediatric to adult health care. Methods Health care providers and nurse case managers in the Complex Care Program (CCP) evaluated health care transition practices prior to 2019, and initiated quality improvement efforts to standardize transition guidance, planning, and documentation from 2019 to 2020 within the CCP. Findings Challenges identified with transitioning CMC include: 1) Varied approaches and timelines for health care providers, 2) Documentation in the EMR, and 3) Connecting to adult health care systems. Throughout this work, CCP staff have learned lessons to effectively transition CMC. Themes included: 1) Transition from a pediatric to an adult primary care provider first, 2) Start transition conversations early, 3) Identify a universal location to document transition planning, and 4) Importance of family involvement. Implications for practice To effectively transition CMC, health care staff must start conversations early, engaging all primary and specialty providers, patients, and families to create safe transition plans.