The book comprises three sections -- "Description, " "Definition, " and "Treatment" -- in which Memmi delineates racism's causes and hidden workings, examines its close affinity to colonialism, and considers its everyday manifestations over a period of centuries throughout the West. His topics include bigotry against Blacks, anti-Semitism, the meaning of "whiteness, " and the status of the Quebecois.

For Memmi, the structure of racism has four "moments":the insistenc on difference; the negative valuation imposed on those who differ; the generalizing of this negative valuation to an entire group; and the use of generalization to legitimize hostility. Memmi shows how it is not racism's content -- which can change at will -- but its form that gives it such power and tenacity.