PCORI is seeking applications to study the comparative clinical effectiveness of alternative features of healthcare systems (e.g., innovative technologies, incentive structures, and service designs) that are intended to optimize the quality, outcomes, and efficiency of care for patients and that have the most potential for sustained impact and replication within and across healthcare systems. Healthcare systems encompass multiple levels (e.g., national, state, and local health environments; organization or practice settings; family and social supports; and the individual patient) and include entities organized to deliver, arrange, purchase, or coordinate healthcare services. PCORI seeks to fund studies that will provide information of value to patients, their caregivers, clinicians, and healthcare leaders concerning which features of delivery systems lead to better patient-centered outcomes (PCOs), so that those features proven to make a difference ultimately affect healthcare delivery.