This book presents the mathematical economic theory of price determination and resource allocation from elementary to advanced levels.General Equilibrium Theory: An Introduction presents the mathematical economic theory of price determination and resource allocation from elementary to advanced levels, suitable for advanced undergraduates and graduate students of economics. This Arrow-Debreu model (known for two of its most prominent founders, both Nobel Laureates) is the basis of modern price theory and of a wide range of applications.General Equilibrium Theory: An Introduction presents the mathematical economic theory of price determination and resource allocation from elementary to advanced levels, suitable for advanced undergraduates and graduate students of economics. This Arrow-Debreu model (known for two of its most prominent founders, both Nobel Laureates) is the basis of modern price theory and of a wide range of applications.General Equilibrium Theory: An Introduction presents the mathematical economic theory of price determination and resource allocation from elementary to advanced levels, suitable for advanced undergraduates and graduate students of economics. This Arrow-Debreu model (known for two of its most prominent founders, both Nobel Laureates) is the basis of modern price theory and of a wide range of applications. The text starts with elementary models: Robinson Crusoe, the Edgeworth Box, and a 2-commodity 2-household 2-firm model. It gives a brief introduction to the mathematics used in the field (continuity, convexity, separation theorems, Brouwer fixed-point theorem, point-to-set mappings, and Shapley-Folkman theorem). It then presents the mathematical general equilibrium model in progressively more general settings, including point-valued, set-valued, and nonconvex set-valued demand and supply. Existence of general equilibrium, fundamental theorems of welfare economics, core convergence, and futures markets with time and uncertainty are treatlc