The objective of this article is to clarify ambiguities in the literature regarding the relationships among three key constructs of work relationships: effort, job performance, and job satisfaction. The relationship between job performance and job satisfaction is of central interest to research in organizational psychology. However, empirical research in that area finds that the link between these constructs is weak at best. A negative effect of effort on job satisfaction is consistent with agency theory, but there is limited empirical evidence to support this assumption. Moreover, some studies have found a positive effect of effort on job satisfaction. Using a model that incorporates the main constructs from agency theory and organizational psychology, the current study finds a negative, direct effect of effort and a positive, direct effect of job performance on job satisfaction. The authors show that conflicting findings in the literature are the result of inconsistency in both the measurement and the definition of constructs across studies that do not fully account for all the relationships between constructs. The current findings emphasize the need to distinguish clearly between factors that represent employees' inputs in a work relationship (i.e., effort) and those that represent their outputs (i.e., job performance). The article also demonstrates the importance of properly accounting or controlling for all key variables to eliminate biases that can arise in empirical research on work relationships. [ABSTRACT FROM AUTHOR]