The aim of this dissertation was to examine two so far separately considered complex constructs, fatigue and mental health, concerning a target group that has to cope with high stress, extraordinary workload, high risks and responsibility: professional pilots. The complexity of the psychophysiological construct fatigue should be highlighted. Potential correlations and interactions of stress with fatigue, sleep problems, mental health and well-being should be investigated. It seemed necessary to consider pilot fatigue not only in the context of sleep medicine, but also in context with the...