The topics of particular importance in contemporary sociology are inequality of educational opportunity (IEO) and mechanisms of social mobility (or immobility). IEO refers to the differences in level of educational attainment according to social background. Social mobility means the differences in social achievement according to social background. When taken in this restricted sense, social immobility can also be called inequality of social opportunity (ISO). This book describes an attempt to synthesize the main findings accumulated by empirical research on these two closely related points. The synthesis takes the form of a simulation model. In the first part of the model a theory is developed leading to some specific conclusions on a number of questions related to IEO. In the second part of the model, the change over time in IEO and in other factors, such as overall average increase in level of educational attainment, is related to ISO. This leads to an examination of the effects on social mobility of the tremendous increase in rates of school attendance that has occurred in most societies since 1945. In varying the model, wide use is made of the impressive set of data collected by The Organization for Economic Cooperation and Development. (Author/JM)