According to Fredrickson's broaden-and-build theory of positive emotions, positive emotions -- such as joy, contentment, and love -- help individuals cope with stress, maintain well-being, and flourish in life. Guided by this theory, this dissertation project conducted three studies which explored the multidimensional influences of positive emotions on stress, coping strategies, resilience, trait anxiety, depressive symptoms, and work engagement. Study 1 examined the mediating role of coping strategies on the link between positive emotions and resilience; in addition, the moderating effect of resilience on the influence of stress toward trait anxiety and depressive symptoms was tested. Study 2 investigated if one's positivity would distinguish differences in their levels of stress, trait anxiety, and depressive symptoms. Finally, Study 3 examined whether stress and positive emotions would account for the variance in work engagement, over and above what has been explained by known predictors -- specifically, work meaningfulness and supervisor support. Path analysis, interaction analysis, multivariate analysis of variance, and hierarchical multiple regression analysis were used to test the different models within these studies. A sample of 200 postdoctoral fellows completed the survey (38% response rate). Results showed that a) coping strategies partially mediated the link between positive emotions and resilience; b) resilience moderated the effect of stress on trait anxiety and depressive symptoms; c) the different categories of positivity distinguished differences in experienced stress, trait anxiety, and depressive symptoms; d) stress and positive emotions accounted for additional variance in work engagement, above what is already explained by work meaningfulness and supervisor support; and e) positive emotions completely mediated the relationship between supervisor support and work engagement. Findings support the broaden-and-build theory's hypotheses that positive emotions enhance adaptive coping strategies and fuel resilience. The data also demonstrated that resilience protected postdocs from experiencing heightened levels of trait anxiety and depressive symptoms by diminishing their relationships with stress. One strategy to optimize health would be to increase opportunities for postdocs to experience positive emotions, which would subsequently spark the upward spiral toward improved coping, greater resilience, and reduced stress, anxiety, and depression. To promote work engagement, it is important for supervisors to not only be mindful of assigning meaningful work to their employees (or help employees find meaning in their work), but supervisors should also be a supportive leader within a positive workplace environment. / text