A term referring to general types of political systems used to organise and manage societies. As a society's population size and territory grow, it must develop new political solutions to keep from splitting apart. In the 1950's, the american anthropologist, elman service described four levels of political integration that have have been used around the world to solve this problem--band, tribe, chiefdom, and state. While there are some unique cultural variations of each of these levels, they are remarkably similar from one society to another. Subsequently, classifying a society in terms of its level of political integration has proven to be a useful tool in comprehending the wide range of human cultures and societies from small foraging communities to modern nation states.