Influencing health behavior through informational campaigns, followed by the expectation of attitude change and subsequent desired behavior changes, is examined. Prior literature in this area indicates that the correlations between information level and overt behavior or between attitude and overt behavior are generally positive though low. Two major approaches to improving the relationships between knowledge, attitude, and behavior are discussed: the approach taken by M. Fishbein and his associates, which argues for the use of measures of behavior intention rather than generalized attitudes, and the approach of W.J. McGuire and other proponents of an information-processing model, which argues that moving between the elements of the knowledge-attitude-behavior continuum demands processing time on the part of individuals and attention to a set of elements within a communication matrix. The five central elements of the communication process--source, message, channel, receiver, destination--and the independent variables involved are examined. The information-processing model is seen as particularly appropriate to health promotion campaigns and is recommended for further careful study in health promotion situations.