Affective states have a profound influence on how people view the world, yet the cognitive consequences of feelings for thinking have received relatively little attention until recently. There is growing evidence that people’s affective reactions have been shaped by evolutionary processes and have an adaptive influence on the way information is processed. There is now extensive evidence for the adaptive benefits of positive and negative affect for the way people think and process social information. Based on recent experimental research, there are two kinds of affective influences: affect congruence, in which an affective state influences the content and valence of thinking, and processing effects, where an affective state has a regulatory influence on the kind of processing strategy adopted. The evidence shows a broad spectrum of affective influences on memory, attention, inferences, associations, and judgments, as well as the way more complex social behaviors are planned and executed. All affective states, including the negative ones, confer significant adaptive benefits, serving as useful inputs to information processing strategies. These experimental findings, and recent theories linking affect and cognition have important practical implications for understanding how affective states influence everyday thinking and behavior.