This chapter reviews the early development of what has been called the Stockholm school of biopsychosocial stress research. This development was facilitated by world-leading endocrinological research at the Karolinska Institute, later rewarded by a Nobel prize to Ulf von Euler. Pioneering work by psychologist Marianne Frankenhaeuser and public health sicentist Lennart Levi explored the interaction between the hormones adrenaline and noradrenaline on the one hand and cognitive behavior and emotional reactions on the other. Studies of the etiology of stress-related ill health followed, and later research programs have used experimental designs, field studies, surveys, and epidemiological methods for the identification of determinants and consequences of work-related stress.