B. M. Meglino and M. A. Korsgaard (2004) argued that rational self-interest varies across individuals and negatively relates to other orientation (OO). OO moderates effects of job characteristics on attitudes, motivation, and helping. Viewing organizations as social dilemmas in which employees face a mixture of competitive and cooperative incentives, the author argues in this article that strength of self-interest links to self-concern (SC), which should be distinguished from OO. SC and 00 are orthogonal and unipolar. Implications are that some propositions by Meglino and Korsgaard need to be rewritten in terms of SC or OO, and that SC is predicted to moderate effects of self-related variables (e.g., job characteristics), whereas 00 might moderate effects of social variables (e.g., team climate) on satisfaction, motivation, and helping. This also implies that when both SC and OO are strong (weak), individual- and group-level constructs are both (in)valid predictors of satisfaction, motivation, and helping.