Addresses the centrality of the self-efficacy mechanism (SEM) in human agency. SEM precepts influence thought patterns, actions, and emotional arousal. In causal tests, the higher the level of induced self-efficacy, the higher the performance accomplishments and the lower the emotional arousal. The different lines of research reviewed show that the SEM may have wide explanatory power. Perceived self-efficacy helps to account for such diverse phenomena as changes in coping behavior produced by different modes of influence, level of physiological stress reactions, self-regulation of refractory behavior, resignation and despondency to failure experiences, self-debilitating effects of proxy control and illusory inefficaciousness, achievement strivings, growth of intrinsic interest, and career pursuits. The influential role of perceived collective efficacy in social change and the social conditions conducive to development of collective inefficacy are analyzed.(2� p ref)(PsycINFO Database Record (c) 2016 APA, all rights reserved)