Curiosity, grit, and persistence over the course of many decades allowed Dr. Harry Hill to master many roles: pediatrician, immunodeficiency expert, laboratory director, NIH-funded researcher, business leader, and mountain climber. In this interview, he discusses the critical role of diagnostic test development in caring for patients with immunodeficiency syndromes. Dr. Hill also talks about the challenges and successes of blending an academic model within a commercial laboratory operation in co-founding ARUP, and then later developing the ARUP Institute for Clinical and Experimental Pathology.