The present study aimed on the one side to examine the differences between work engagement and workaholism in terms of their associations with health and well207 being, as well as with other aspects of the relational and working domains; on the other side it aimed to explore the nature of the relationship, both linear and non-linear, between work engagement and workaholism. 208 School Principals (65.9% female) filled out a well-validated questionnaire. The results of the structural equation modeling confirm that work engagement and workaholism are two distinct constructs, whose associations with employee well-being are different. On the contrary there was no relationship between work engagement and workaholism, either linear or curvilinear.