Scholars vary in their emphasis on the importance of the nature of the stressor event in determining and shaping people’s reactions and the ways they cope with it. For example, Hill (1949), who developed one of the first models for understanding coping with stress on the basis of his work with American families who experienced the drafting to and release from military service of men in the Second World War, identified diverse responses to stress based on its source, whereas Calhoun and Tedeschi (2006) posited that the effects of the event on people’s assumptive world rather than the characteristics of the event itself are the key to understanding responses to stress. The nature of stressful events can vary greatly as do the ways for classifying them. Dimensions typically used for the classification of stressor events include their source, nature, severity, intensity, duration, and controllability. The following sections address commonly used dimensions to classify stressor events. For clarity, these dimensions are presented as a dichotomy although in reality the picture is more complex.