Thinking about what might have been – counterfactual thinking – is a common feature of the mental landscape. Key questions about counterfactual thinking center on why and how they occur and what downstream cognitive and behavioral outcomes they engender. The functional theory of counterfactual thinking aims to answer these and other questions by drawing connections to goal cognition and by specifying distinct functions that counterfactuals may serve, including preparing for goal pursuit and regulating affect. Since the publication of our last theoretical statement (Epstude & Roese, 2008), numerous lines of empirical evidence support, or are rendered more readily understandable, when glimpsed through the lens of the functional theory. Howeve...