Older adult patients and family caregivers face numerous safety challenges when transitioning from the hospital to skilled home health (HH). This article describes how older adults and their family caregivers, HH frontline providers, HH leadership, and HH hospital-based transition coordinators, were engaged to identify best practices to implement the Hospital-to-Home Health Transition Quality (H3TQ) Index. This participatory co-design process identified ways patients, caregivers, and staff differ in how and when to administer the H3TQ Index, confirming the importance of engaging a wide range of stakeholders in design processes.