Sixteen recent longitudinal studies are examined for evidence relevant to the claim that a change to one's employment status affects one's mental health. Although there were limitations to the set of studies examined, most of the studies supported this claimed relationship. Examination was then made of the size of this effect. In carrying out this examination, the set of study results were divided into two categories: (a) those addressing the question of the extent to which gaining employment impacts on mental well-being; (b) those addressing the question of the extent to which employment loss impacts on mental health. The meta-analyses indicated that there was a weighted effect size of .54 for the first question, and a smaller weighted effect size (.36) for the latter question.