Previous studies have shown that situations relevant for human mating can affect the levels of many hormones. This study focused on the hypothalamus-pituitary-adrenal axis by measuring salivary cortisol levels in 84 young men prior to and after a period of short social contact with a woman or man. Results showed that after contact with another man the cortisol levels of the participants declined according to the circadian release pattern of cortisol. However, cortisol levels in men declined less when they had contact with a woman. Furthermore, cortisol levels of men increased when they perceived the woman with whom they had contact as attractive. Our findings provide indirect evidence for the role of the hypothalamus-pituitary-adrenal axis in human courtship. During social contact with attractive women, moderate increases in cortisol levels may reflect apprehension over an opportunity for courtship. ?? 2010 Elsevier Inc.