Functionalist systems theories. The theorists in this tradition explain the emergence and/or maintenance of parts, structures, institutions, norms or cultural patterns of a social system in terms of their consequences, that is, the particular functions each realizes or satisfies. This includes, for instance, their contribution to the maintenance and reproduction over time of the larger system. The major functionalist in sociology is arguably Talcott Parsons.

p. 1. - Systems theories (2006)