I believe that my most important scientific contribution has been to participate in a decades-long collaboration with many fine colleagues in a program of research exploring the perception of risk. I shall briefly review the path this research has taken, its main contributions, and its importance to science and society.

The origins of this research can be traced to 1959, my first year as a graduate student in psychology at the University of Michigan. I was assigned to work for Professor Clyde Coombs and became fascinated by a study Coombs was doing in which he examined people's preferences among gambles. I replicated and extended this study for my first-year project. The following year I began to work with Ward Edwards, who was also studying risk-taking and decision-making. In Edwards’ laboratory I met Sarah Lichtenstein. After graduate school, Lichtenstein and I went our separate ways, but we were reunited in Eugene, Oregon, in 1966, and worked together for more than forty years.

In 1970, I was introduced to Gilbert White, a famed geographer and pioneer researcher in risk perception, who asked if the laboratory studies on decision-making that Lichtenstein and I had been doing could provide insight into some of the puzzling behaviors he had observed in studying human responses to natural hazards. Much to our embarrassment, we realized that our studies had been too narrowly focused on choices among simple gambles to tell us much about risk-taking behavior in the flood plain or on the earthquake fault.

White's questions were intriguing, however, and, with economist Howard Kunreuther, we turned our attention to natural hazards, attempting to relate behavior in the face of such hazards to principles that had been emerging from psychological studies of probabilistic judgments and risky choices. We found the work that Amos Tversky and Danny Kahneman had been doing on heuristics and biases in probabilistic thinking to be particularly valuable in explaining people's failures to take adequate precautions against the threats posed by natural hazards.

The mid-1970s was a time when concerns about pesticides and nuclear power were rapidly increasing, and we soon found our attention drawn to technological hazards.