He is a board certified family physician and specialist in occupational and environmental medicine. He directs the UW Center for One Health Research, which explores the connections between human health, animal health, and the environment. His current research focuses on zoonoses (infectious diseases between animals and humans), animals as "sentinels" for human environmental health hazards, and increasing clinical collaboration between human health care providers and veterinarians. He is co-editor, with Lisa Conti DVM, of the clinical manual: Human-Animal Medicine: Zoonoses, Toxicants and other Shared Health Risks.