This entry discusses information processing, or the ways in which people obtain, selectively transform, and store information that can affect political attitudes, beliefs, and behaviors. It first reviews the development of classic, constructivist, and dual-processing models of information processing. Situating the discussion in the realm of political information processing, it then reveals how motivated reasoning, as well as other contextual and individual-level differences (e.g., partisan cues, framing, trust, political knowledge, and the need for cognition), are associated with heuristic and deliberate processing.