A band society is the simplest form of human society. A band generally consists of a small kin group, no larger than an extended family or clan. Bands have very informal leadership; the older members of the band generally are looked to for guidance and advice, but there are no laws and none of the coersion seen in more complex societies. Bands' customs are almost always transmitted orally. Formal social institutions are few or non-existent. Religion is generally based on family tradition, individual experience, or counsel from a shaman. Band societies usually hunt and gather to obtain their food. (See Subsistence)

In his 1972 study, The Notion of the Tribe, Morton Fried defined bands as small, mobile, and fluid social formations with weak leadership that do not generate surpluses, pay no taxes and support no standing army.

Bands are distinguished from tribes in that tribes are generally larger, consisting of many families. Tribes have more social institutions, such as a chief or elders. Tribes are also more permanent than bands; a band can cease to exist if only a small group walks out. Many tribes are in fact sub-divided into bands; in the United States, some tribes are made up of official bands that live in specific locations.

With the spread of the modern nation-state to all corners of the globe, there are very few true band societies left. Some historic examples include the Inuit of northern North America, the Shoshone of the Great Basin, the Bushmen of southern Africa, and Australian Aborigines.