Tiredness is a frequent complaint in the labour sphere, but difficult to analyse. Works that sought to produce an explanatory theory of tiredness ran up indeed against the subjective and multidimensional dimension of the phenomenon. From there comes the will of many specialists in tiredness at work to concentrate their studies on what would constitute the psychosocial dimension of tiredness in the industrialized and tertiarized economies: boredom, monotony and mental suffering. If these researches made it possible to widen our comprehension of the question of tiredness at work, they remain marked by an implicit representation of a human being equipped with invariant psychological and social needs. Thus they do not make it possible to accoun...