Dispositional sources of job satisfaction have been the subject of recent research in the organizational sciences. Problems in much of this research, which limit the conclusions one can draw from the results, are discussed. This study makes a distinction between affective disposition, defined as the tendency to respond generally to the environment in an affect-based manner, and subjective well-being, the level of overall happiness and satisfaction an individual has with his or her life. Affective disposition was hypothesized to lead to subjective well-being, and subjective well-being and job satisfaction were hypothesized to be mutually causative. A causal model was tested employing two different sources of data: self-reports and "significant other" evaluations. This biangulation of sources of data and estimation of nonrecursive relationships removes some problems often assumed to plague results based on single source data. Results indicated support for the overall hypothesized causal model and supported a dispositional influence on job attitudes. The influences are more complex than past research has suggested.