The purpose of this study was to examine the relationship between potential stressors and stress symptoms mediated by family adaptability and cohesion. This study also examined whether the Family Adaptability and Cohesion Scale (FACES III) provides data to support Olson's Circumplex Model of Marital and Family Systems. That is, the results of the present project were used to supplement the current debate over FACES III's curvilinearity. The data used in this sample are the data from a two-year research project about commercial airline pilots. The first hypothesis tested whether the FACES III sub-scales; cohesion and adaptability were linear measures or curvilinear measures. The second was that those individuals who had higher levels of family functioning would have fewer stress symptoms, while taking number of potential stressful life events into account. The results for the cohesion sub-scale supported using it as a linear measure. The results for the adaptability sub-scale were inconclusive. The results also demonstrated that life events and cohesion were Significant predictors of stress and that family cohesion is a mediating factor in the relationship between potential stressors and experienced stress symptoms. / Master of Science