Analogue scales are relatively easy to interpret for the assessment of exercise-induced dyspnea although certain standardization points remain to be established. We discuss the pathophysiological basis correlating dyspnea with exercise parameters. In clinical practice, the curve of the dyspnea/ventilation ratio plotted during exercise is a useful parameter, focusing attention on the notion of a dyspnea threshold (near the ventilatory threshold) and slope (which could be modified, for example, by treatment or a rehabilitation program). Evaluation of exercise-induced dyspnea must of course be an integral part or the overall analysis of all other parameters studied during exercise.