The idea of stratification refers to the idea of vertical segmentation in a sense of having more or less resources. Degrees of stratification are always relational and they express degrees of social inequality. Open stratification systems are given when a society leaves channels for upward- or downward mobility, where actors or families can change their position inter- or intragenerationally. The paper discusses middle strata in stratified societies which are between poor and rich households. In the sociology of change, middle classes have always held a central function. Middle classes serve as a kind of conflict buffer of modern societies. In his discussion why there is no socialism in the United States which was questioned in book format by Werner Sombart in 1906, the upcoming middle classes and their related relative wealth played a central role. Sombart argued that if people earn means to engage in different consumption activities they start to arrange positively with a political-economic system receiving a status, which is worth defending. With roast beef and apple pie all socialist dreams disappear, was somehow the answer by Sombart to the stability of capitalism in early 20th century. According to Collins (2013), technological displacement of middle-class labour is not much more than thirty years old; while it took almost 200 years to destroy the working-class labour force, computerization of middle-class labour is proceeding at a much faster pace than the mechanization of the manual labour force. Therefore, none of the previous ways to compensate job losses will work effectively anymore in the future. The paper will argue theoretically as well as trying to provide empirical findings on developments in recent international societies looking at convergencies and divergencies of middle class developments.