This paper focuses on economic and financial asymmetries by addressing methodological issues related to the meaning of economic asymmetries and how such asymmetries arise in markets, general equilibrium modeling and in national and global economies. The methodology of modeling asymmetric information began with Akerlof's celebrated model of “lemons” and while these asymmetries were quickly adopted in microeconomics, macroeconomics, business cycles and related areas, economic policies adapted the concept of asymmetries to highlight the importance of unequal magnitudes of responses among economic and financial variables. We discuss numerous topics that illustrate the large scope of economic and financial asymmetries in actual economies and their modeling to establish their methodological centrality in economic analysis and policy.