However, less than 1% of the studies of cognitive dissonance have also investigated individuals’ personality traits. Individual differences might be quite important in moderating the strength of dissonance effects. “Cognitive dissonance” is a frequent occurrence in our daily life. The purpose of the study in this book is to investigate the relationships between personality traits and cognitive dissonance in a counter-attitudinal advocacy paradigm, with a special focus on the traits of openness to experience and strength of sense of self, and to examine whether the relationships in a novel on-line survey study form were different from the relationships in the standard laboratory setting! Although cognitive dissonance is a common occurrence in most people’s everyday life, the magnitude of the dissonance they experience may nonetheless differ from one person to another.