Explores strategies to achieve system-level impact for a nonprofit focused on addressing patients' basic social needs through healthcare institutions. Founded in 1996 with a volunteer-staffed help desk at Boston Medical Center connecting low-income patients with basic resources like heating assistance, job training, and childcare programs, by 2013 the nonprofit had grown to 6 cities and 1,000 volunteers serving over 11,000 patients annually. At the end of a successful "proof plan" period, Health Leads Co-Founder and CEO Rebecca Onie and her team faced the question of how to make meeting patients' social needs a standard part of health care in the U.S.: replicate Health Leads' proven model or instigate a social care movement?