The central theme of this session is the changing relationship between “orthodox” (i.e., mainstream, neoclassical) and “heterodox” economics, especially in the USA, during the past two or three decades. Economics is such a large and heterogeneous discipline that it cannot be characterized both briefly and accurately. Alongside the growth of formalization and mathematization, and the high degree of uniformity in the undergraduate and graduate curricula and in the leading textbooks, there are also within the subject a number of dissenting or deviant doctrinal schools, rival methodological approaches, and innovative developments designed to remedy its defects and/or overcome its limitations. Moreover, many of the outspoken criticisms of the status quo, proposed remedies, and innovations, originate with or are endorsed by prominent economists with impeccable professional credentials. Indeed, in some cases their contributions threaten the discipline's foundations and can, therefore, be considered a species of “orthodox subversion.”