Exercise testing is fundamental for the accurate quantification of cardiorespiratory fitness and for identifying mechanisms underlying exercise intolerance and shortness of breath (dyspnoea). Several indices of exercise testing-related physiological response relate independently to major clinical outcomes such as survival and hospital admissions, thus allowing considerable improvement in prognostic stratification. This course is designed to provide a comprehensive understanding of the physiological basis of exercise testing, to identify the indications and the protocols used in clinical and rehabilitation settings as well as the increased importance of exercise testing in the prognostic setting.