摘要:In 1942, Gordon Allport pointed out that “Psychology needs to concern itself with life as it is lived” (as cited in Bolger, Davis, & Rafaeli, 2003). Following this recommendation requires studying people’s thoughts, feelings, and behaviors in situ: when and where they actually take place. Is this even possible? Around 30 years after Allport’s call, Csikszentmihalyi, Larson, and Prescott (1977) conducted a study regarded to be the first to use this approach (Iida, Shrout, Laurenceau, & Bolger, 2012). In the course of one week, researchers assessed daily activities of twenty-five adolescents put forward in response to 753 random beeps produced by their pagers. The authors called this novel methodology the experiential sampling method. Since then, ecological validity and reduced recall bias have been listed among the main strengths of intensive longitudinal designs, where data are collected from one to several times a day for at least a few days. Moreover, recent technological advances, such as smartphones or fitness trackers, have provided new possibilities for studying experiential, physiological, and behavioral processes in their natural settings. As a result, the number of such studies has grown exponentially (see: Hamaker & Wichers, 2017). The aim of this Special Issue is to point towards the opportunities that these methods provide and to showcase examples of diary studies conducted across distinct subdisciplines of social psychology.