In this interview, David Zierler, Oral Historian for AIP, interviews Douglas Brash, Professor in the Department of Therapeutic Radiology in the Yale School of Medicine. Brash recounts his childhood in a rural community outside of Cleveland, and then in Chicago, and he describes his early interests in science and his determination to become a physicist by the third grade. He discusses his education at Illinois where he majored in engineering physics, and he describes his formative summer job at Livermore Laboratory which helped to compel him to pursue biophysics for graduate school. Brash discusses his research at Ohio State under the supervision of Karl Kornacker, and the work of his graduate adviser, Ron Hart who was focused on DNA repair. Brash discusses his interests in aging and molecular biology which was the foundation for his dissertation, and he provides an overview of biophysics as a discrete field in the 1970s. He discusses the distinctions in his research regarding basic science and clinically relevant therapies as it relates to understanding cancer, and he describes the varying interests in environmental carcinogenesis and retroviruses as a basis for cancer research. Brash explains the origins of the discovery of oncogenes and the connection leading to his specialty in skin cancer research. He describes his postdoctoral research at Harvard and the Dana Farber Institute with Bill Haseltine working on DNA damage and mutagenesis. Brash discusses his subsequent work at the NIH where he continued his research in cell mutation and where he began to study the effect of UV rays on skin cancer. He explains the circumstances leading to his decision to join the faculty at Yale, where he realized he had greater opportunity to continue examining UV rays and skin cancer. Brash offers an overview of the major advances over the last two decades in skin cancer research, and he describes the central importance in DNA sequencing and Chemiecxitation. He discusses the many research advantages associated with having an appointment in a medical school, and at the of the interview, Brash describes the value of bringing a physics approach to cancer research, and some of the policy and communication implications that come with working at the cutting edge of the field.