Successful antibiotic stewardship programs have a designated leader or co-leader who are accountable for the program and outcomes. Many hospitals effectively use a co-leadership model with an infectious diseases physician and pharmacist, and others are led by a pediatric infectious diseases physician. ASPs with physician-pharmacist co-leaders should set clear expectations of responsibilities of each co-leader. In circumstances when an infectious diseases-trained physician leader is not available, other physician ASP leaders or co-leaders could be hospitalists, adult ID physicians, or other physicians interested in improving the use of antibiotics. In 2018, the median FTE for a pediatric infectious diseases physician at 60 United States’ children’s hospitals was 0.3 (IQR: 0.14 to 1.0).