Workaholism has been shown to be detrimental to individuals mental and physical health, and is often associated with low job satisfaction, poor quality of life, sleep problems, and conflicts in work-family relationships. There is robust evidence that it acts as an antecedent of burnout syndrome, anxiety, and depression. Nursing is among the professions most affected by this phenomenon, which denotes harm not only to this professional category, but also to its clientele, their families, and institutions. This thesis consists of four studies conducted independently of each other, within a single context that sought to understand, analyze, and discuss the performance of nursing professionals and their relationships with workaholism. The first study is an integrative review that aimed to understand the relationship between workaholism and burnout syndrome, analyzing scientific material developed in the last decade. The second study aimed to qualitatively analyze the perceptions of 20 nursing professionals seeking parallel training, investigating their motivations and possible associations with states of engagement and workaholism. It was concluded that the search for parallel training among nursing professionals does not necessarily reflect addictive behavior. The third study investigated the mediating role of job crafting actions in the relationships between engagement, work addiction, and job resources in 765 nursing professionals. It was found that occupational self-efficacy and job crafting opportunities act as predictors of engagement levels, while demand levels acted as predictors of work addiction. It was observed that the task crafting dimension acts as a mediator in these relationships. Finally, the fourth study analyzed evidence of validity of the Brazilian version of the Bergen Work Addiction Scale (BWAS) seeking to understand the relationships between work addiction, anxiety, and sociodemographic variables. The results indicated that the adapted version of the Bergen Work Addiction Scale presented evidence of convergent and criterion validity, being a reliable instrument to assess work addiction. The studies presented in this thesis indicate that workaholism is a reality in contemporary society and that research on this phenomenon has not yet reached a consensus on its definition and measurement methods. Proposals for interventions and treatment are discussed throughout the studies.