The Theory of Reasoned Action states that individual performance of a given behavior is primarily determined by a person's intention to perform that behavior.  This intention is determined by two major factors:

1. the person's attitude toward the behavior ( beliefs about the outcomes of the behavior and value of these outcomes).
2. the influence of the person's societal environment or subjective norm (beliefs about what other think the person should do).

Key Authors:   The Theory of Reasoned Action (Fishbein & Ajzen 1975; Ajzen & Fishbein 1980) 

The Theory of Planned Behavior adds to the theory of reasoned action by adding the concept of perceived control over the opportunities, resources, and skills necessary to perform a behavior.  This is similar to Bandura's concept of self-efficacy (See section on Social Learning Theory)

Key Concepts: behavioral attitudes, outcome expectations, values, subjective norms, beliefs of others, motive to comply with others, perceived behavioral control.

Key Authors:   The Theory of Planned Behavior ( Ajzen 1985, 1988)