Microeconomics has contributed the principle of diminishing marginal utility, according to which most people are averse to risk, while some are neutral to risk and others are risk seekers. For the latter, greed may be a personality trait, as demonstrated both by the fictional financier in the movie "Wall Street" and by the actual history of Leona Helmsley. In addition, greed may not be a unitary phenomenon. Instead, it may be either a true pathology of personality or a rationally motivated approach to risk taking. Obtaining direct accounts of offenders' throughts and experiences will be needed to explore these possibilities in more time. In the meantime, the presentence reports studied by Rothman and Gandossy as well as the author indicate that offenders were preoccupied with avoiding falling back rather than with getting ahead. In addition, Kahnemann and Tversky have developed an S-shaped loss function in which offenders' fear of falling below their current economic level is the main motivation for their crimes. Further research should examine these issues, as well as the possible existence of organizational and cultural parallels. Figures, notes, and 27 references