unit in Philadelphia to care for the sickest of children. Before the creation of a PICU at CHOP, children who required advanced care were often cared for on the surgery wards and recovery rooms. Most of these children were cared for by anesthesiologists in the recovery room. Fourth hospital 1974–present Construction of the new hospital at a new site on the west side of the Schuylkill River at 34th Street and Civic Center Boulevard, adjacent to the campus of the University of Pennsylvania, was begun in 1969 and the first building was opened in 1974. This present Children's Hospital complex occupies part of the site of the old Philadelphia General Hospital and Blockley Almshouse. A helicopter transport system for critically ill and injured children was inaugurated in 1973. Milestones and advances in pediatric care pioneered at CHOP include the first formal medical training in pediatrics, techniques for the correction of congenital heart malformations, incubators for newborn intensive care, home ventilator care, and vaccine development. In October 2006, Children's Hospital of Philadelphia's trauma center was one of the receiving hospitals' for victims of the West Nickel Mines School shooting, treating a few of the pediatric victims from the shooting who were medevaced to the hospital. The Children's Hospital of Philadelphia is in Philadelphia's University City neighborhood, and since 2001 has been undergoing a $1.5 billion expansion that has doubled the hospital's size, while also building more than one million square feet of new research and outpatient facilities on a large, eight-acre site south of the main hospital on Civic Center Boulevard. The South Campus expansion includes the eleven-story Colket Translational Research Building, which provides lab space for the Center for Childhood Cancer Research and the Center for Cellular and Molecular Therapeutics. The new South Campus also includes an underground parking garage and an ambulatory care building with outpatient services. This South Campus expansion adjoins the University of Pennsylvania Health System's construction of the Perelman Center for Advanced Medicine and Roberts Proton Therapy Center. On July 1, 2015, Madeline Bell, previously CHOP's president and chief operating officer, became president and chief executive officer. She succeeded Steven M. Altschuler, MD, who retired after 15 years as CEO. The board of trustees of Children's Hospital made the announcement on May 14. Later that year, in October 2015, the expansion of the Brandywine Valley Specialty Care and Ambulatory Surgery Center was opened. This is a