Dr. Hemenway teaches classes on injury and on economics. He has won ten teaching awards at Harvard School of Public Health.
Dr. Hemenway has written widely on injury prevention, including articles on firearms, violence, suicide, child abuse, motor vehicle crashes, fires, falls and fractures. He headed the pilot for the National Violent Death Reporting System, which provides detailed and comparable information on suicide and homicide.
In articles on insurance, Dr. Hemenway described a general reason why low-risk individuals often buy insurance, and coined the term "propitious selection." Recent economic studies have focused on empirically determining which goods are more and less positional (e.g., bought largely to "keep up with the Joneses"). An early statistics article, Why Your Classes are Larger than Average, has been anthologized in various mathematical collections.