Social change is ubiquitous. Although earlier social scientists often treated stability as normal and significant social change as an exceptional process that required a special explanation, scholars now expect to see change at all times and in all social organizations. Much of this type of change is continuous; it occurs in small increments and reveals long-term patterns such as growth. Discontinuous changes, however, are more common than has been assumed. From the perspective of individual organizations, these changes are relatively common and often result in sharp departures from previous states such as when corporations are created, merged, or terminated. From the perspective of larger populations of such organizations, relatively few discontinuous changes result in comparably sharp departures from long-term patterns and trends. Even revolutions that result in dramatic changes of political and legal institutions generally do not transform all of society equally. Some previous patterns continue...