While intensive and ongoing research on the determinants of marital stability has resulted in the identification of a large number of risk factors, the question of why there has been a nearly continuous upward trend in divorce rates in many developed countries has yet to be answered. This upward trend continued over a period of more than one hundred years, and ended-at least in some countries-in the late twentieth century or early twenty-first century. The aim of this paper is to review the theoretical concepts and the empirical findings of studies that have investigated historical trends in divorce rates. Some authors have argued that the quality of marriages has declined, while others have attributed this trend to a weakening of the barriers to divorce, or to increased opportunities to meet alternative partners. Theories of social change generally emphasize the role of either modernization or normative change in marital dissolution patterns. Given the evidence that the cohort and the period effects on the divorce rate cannot be explained by socioeconomic variables, it seems likely that increasing divorce rates are better explained by cultural than by socioeconomic changes.