Social planner - Definition and Overview

In welfare economics, a social planner is a decision-maker who attempts to achieve the best result for all parties involved. In neo-classical welfare economics, this means the maximization of a social welfare function. In modern welfare economics, there is more of an emphasis on Pareto optimality, in which no one's outcome can be improved without worsening someone else's outcome. Pareto-optimal solutions are not unique, and according to the Second Fundamental Theorem of Welfare Economics, a social planner can achieve any Pareto-optimal outcome by an appropriate redistribution of wealth.

In practice, the social planner role is generally played by a government. It should be noted, however, that real governments have incentives other than the benefit of their people. This problem is studied in public choice economics.