Class in the U.S. is usually defined in terms of income and status. The “middle class” denotes the majority who are neither poor nor rich. This descriptive way of looking at class obscures more than explains—for example, how someone gets rich who doesn’t work at all while someone else who works hard is poor. Marxism defines classes by their relationship to the control, and generation, of wealth production. Someone who makes money from the labor of others is part of the capitalist class; a worker whose wage labor enriches others is part of the working class; and someone with an intermediate position such as small owners, managers, and highly-paid professionals are part of the middle-class. This talk will examine the Marxist conception of those class dynamics.