Principled and expedient ideologies guide people along different ethical paths. A principled ideology, indicative of higher claimed integrity, involves a stronger personal commitment to a moral identity that facilitates positive social activities and helps resist the temptation of illicit activities. Prior research shows that individual differences in integrity are accurately perceived by friends, are reflected in self-beliefs, and affect social judgment. Results of four studies showed that integrity (a) predicts reported antisocial activities (lying, cheating, stealing) even after controlling for other individual difference measures, (b) predicts reported helping and volunteering, especially for nobler reasons and after controlling for empathy, and (c) is associated with a variety of personality and attitudinal qualities that signify greater psychological well-being, buffering from stress, and effective social functioning.