["Oxford Bulletin of Economics and Statistics, EarlyView. ", "\nABSTRACT\nThis paper offers a simple model to evaluate and measure inequality of opportunity in a multiperiod framework, in which both circumstances and effort may change over time. We adopt a norm‐based approach and an axiomatic methodology: we first characterise two alternative definitions of a ‘fair distribution’, associated respectively with the ex ante and ex post views of equality of opportunity; then we characterise a family of indexes of multiperiod inequality of opportunity expressed as an appropriate distance between the fair and the actual distributions. The proposed framework is then applied to evaluate the Korean distribution of income from a multiperiod and opportunity egalitarian perspective.\n"]