This paper presents an economic theory of self-control, arguing that self-control is a fundamental aspect of decision-making that has been overlooked in traditional economic models. The authors propose a model in which individuals are viewed as organizations with two separate entities: a planner who makes decisions in the long term and a doer who acts in the short term. This two-self model allows for the analysis of self-control as a control problem, similar to agency problems in organizations. The paper discusses the concept of dynamic inconsistency, where individuals' preferences change over time, leading to conflicting decisions. Strotz's model is re-examined, and the authors argue that his model is incomplete because it does not account for the existence of a planner and a doer. The authors propose that self-control is a problem that requires the use of control mechanisms, such as precommitment, to align the planner's long-term goals with the doer's short-term actions. The paper also explores the role of institutions in promoting self-control, such as Christmas clubs, mandatory pension plans, and social security. These institutions help individuals resist short-term temptations by limiting their flexibility. The authors argue that these institutions are effective because they align with the planner's long-term goals. The paper concludes that self-control is a crucial aspect of economic behavior that has been underappreciated in traditional economic models. The authors propose a new framework for understanding self-control that incorporates the concept of a planner and a doer, and highlights the importance of control mechanisms in aligning long-term and short-term goals. The paper also emphasizes the importance of institutions in promoting self-control and the need for further research on the economic implications of self-control.This paper presents an economic theory of self-control, arguing that self-control is a fundamental aspect of decision-making that has been overlooked in traditional economic models. The authors propose a model in which individuals are viewed as organizations with two separate entities: a planner who makes decisions in the long term and a doer who acts in the short term. This two-self model allows for the analysis of self-control as a control problem, similar to agency problems in organizations. The paper discusses the concept of dynamic inconsistency, where individuals' preferences change over time, leading to conflicting decisions. Strotz's model is re-examined, and the authors argue that his model is incomplete because it does not account for the existence of a planner and a doer. The authors propose that self-control is a problem that requires the use of control mechanisms, such as precommitment, to align the planner's long-term goals with the doer's short-term actions. The paper also explores the role of institutions in promoting self-control, such as Christmas clubs, mandatory pension plans, and social security. These institutions help individuals resist short-term temptations by limiting their flexibility. The authors argue that these institutions are effective because they align with the planner's long-term goals. The paper concludes that self-control is a crucial aspect of economic behavior that has been underappreciated in traditional economic models. The authors propose a new framework for understanding self-control that incorporates the concept of a planner and a doer, and highlights the importance of control mechanisms in aligning long-term and short-term goals. The paper also emphasizes the importance of institutions in promoting self-control and the need for further research on the economic implications of self-control.