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Time pressure brought about by work or other activities is a real problem in modern society. Humans are required to do things faster and faster. As revealed in both informal language and in ergonomics literature, time pressure is a factor in psychological stress. Paradoxically, despite the current challenge to reduce time pressure, its mechanisms and consequences are still insufficiently studied. Factors to be taken into account in the analysis of the causes and consequences of time pressure, be it acute or chronic, are illustrated in two fields: the route and the work. Arguments are built from bibliographic data and from results obtained by the authors during surveys, experiments and activity analysis involving child pedestrians, car drivers and employees of call centres. The subjective nature of time pressure is put forward. Strong links between organisational time constraints and cognitivo-emotional individual factors are illustrated throughout the process. Time pressure has been described as resulting from an unfavourable ratio between the amount of time that is required to accomplish a task and the amount of time that is available. The insufficiency of a chronometric approach is also highlighted. The presence of a sanction if the task is not completed in time has also been previously seen as a main determinant of time pressure. In line with this idea, motivation sometime appears to be sufficient for time pressure elicitation; however, it is not a necessary condition for either. Indeed, the incidence of cross-situational contagion supports the fact that time pressure may extend to nearly all of an individual?s activities without the scope for specific motivation. Other time-pressure related factors have been identified, including task complexity and multi-tasking, despite the fact that the latter?s primary purpose is actually to save time. In addition, uncertainties, operating margins and flexibilities, and break efficacy have to be examined. Finally, personality characteristics, especially type A, need to be considered in this framework. The consequences of time pressure on behaviour and emotions are discussed in terms of negative impacts, as well as in terms of positive impacts at individual and/or organisational levels. To conclude, the authors propose a comprehensive definition of time pressure. Methodological issues to better address the study of time pressure are outlined in the field of experimental research, but above all in the field of management in ergonomics.