In war-torn Bosnia in 1993, Dr. Michael VanRooyen learned firsthand the dangers humanitarian aid workers face when he worked in a monastery that had been converted into a trauma hospital. “All the windows were boarded up with planks to keep the shrapnel from coming in and injuring staff and patients,” Dr. VanRooyen recalls. “The shelling was pretty active.” That wasn’t Dr. VanRooyen’s first brush with danger while caring for those desperately in need. In 1986, he was organizing relief efforts for Rwandan refugees. “I was carrying relief supplies to a hospital in Zaire,” he says. “After I landed, I was held captive by the Zairan military for five days. They accused me of being a military adviser.”

Now, as codirector of the Harvard Humanitarian Initiative (HHI), Dr. VanRooyen works to make sure aid work in challenging areas is as safe as possible. He’s spent much of his career working with such organizations as Save the Children, International Medical Corps, and CARE. Early on, he recognized some of the obstacles that make it difficult to provide aid in areas afflicted by war and natural disasters. “I was in Somalia,” he says. “There was this one little girl in worse shape than the rest. She was an orphan. I remember asking through a translator, ‘How can a family not take her in?’ But one woman showed me her own hut, an enclosure made of plastic sheeting, burlap, and cardboard — with her two sick kids. ‘This is the choice I have,’ she said.”

Emergency care was Dr. VanRooyen’s specialty when he completed his residency at the University of Illinois Chicago Medical Center in the late 1980s. After earning his master’s in public health, he founded the Johns Hopkins Center for International Emergency, Disaster, and Refugee Studies. Since 2004, VanRooyen has been with the HHI, which aims to advance the effectiveness of international relief efforts. As he explains, “Many people who enter the field of humanitarian assistance get on-the-job training. I became interested in finding ways to professionalize the humanitarian community.”

Dr. VanRooyen, who also practices at Brigham and Women’s Hospital in Boston, says his work in emergency medicine influences his other work. “You need to take care of sick people on the spot. In many ways, emergency medicine is to the medical world what humanitarian assistance is to international health.”