Social exchange theory

Origins and core ideas

Sociologist George Homans presented social behavior as exchange in 1958, and Peter Blau extended the approach to power and institutions. In social psychology, John Thibaut and Harold Kelley analyzed how the outcomes of each person depend on those of the other.

• Reciprocity: benefits create an expectation of return
• Comparison level: the outcomes a person feels they deserve
• Comparison level for alternatives: what could be obtained elsewhere
• Power: the party less dependent on a relationship has more leverage

Social versus economic exchange

Blau separated economic exchange, with terms fixed in advance, from social exchange, in which obligations are unspecified and rest on trust. This distinction became influential in organizational research, where employees who feel supported are said to reciprocate with commitment and effort.

Criticisms

Critics worry that if any behavior can be recast as rewarding, the theory explains everything and predicts little. Costs and rewards are hard to measure and vary by person. Communal relationships, in which people give according to need instead of keeping score, may follow different norms, as Margaret Clark and Judson Mills argued. Research in this tradition also relies heavily on correlational surveys. Cropanzano and Mitchell's review documents considerable conceptual variety in how exchange is defined and applied.