Conflicting reports exist as to whether air traffic controllers (ATC) have an increase in blood pressure (BP) and prevalence of hypertension because of the stressful nature of their job. We have addressed the issue in male ATC working at the Linate airport of Milan. A total of 80 ATC participated, and the 24 h blood pressure monitoring was obtained during two working shifts separated by one night of rest. Blood pressure was measured conventionally and by 24 h ambulatory monitoring; data were compared with those of an age matched male sample three times as large, selected from the data of the Studio delle Pressioni Ambulatoriali delle Loro Associazioni (PAMELA), ie, a large sample representative of the population of the nearby town of Monza. Treated hypertensive subjects were excluded from both groups. Conventional diastolic BP and heart rate were similar in ATC and controls, whereas conventional systolic BP was significantly greater in the former than in the latter group. No difference, however, was seen between ATC and controls as far as ambulatory BP and heart rate were concerned; namely, 24 h, day, and night average systolic BP, and diastolic BP and heart rate were similar in the two groups. Thus daily life BP is not increased in ATC. This may result from the fact that, being a highly selected group with suitable training, these subjects adequately cope with the stress inherent to the job.