The purpose of this paper was to introduce the W.J. McGuire's(1985) "communication/persuasion matrix" model and his review on persuasion studies from the viewpoint of the model. The paper consists of the following three parts. (1) Introduction. (2) An input/output analysis of persuasive communication : (a)components of the model, (b)evaluation of the communication/persuasion matrix. (3) Soruce variables' effects on persuasive impact : (a)the credibility-attractiveness-power analysis, (b)source credibility variables, (c)source attractiveness variables, (d)source power variables, (e)effects of source demographics, (f)output steps that mediate source effects, (g)effects of message pairing on source valence.