Empirical research on workaholism has been hampered by a lack of consensus regarding the definition and appropriate measurement of the construct. In the present study, we first review prior conceptualizations of workaholism in an effort to identify a definition of workaholism. Then, we conduct a meta-analysis of the correlates and outcomes of workaholism to clarify its nomological network. Results indicate that workaholism is related to achievement-oriented personality traits (i.e., perfectionism, Type A personality), but is generally unrelated to many other dispositional (e.g., conscientiousness, self-esteem, positive affect) and demographic (e.g., gender, parental status, marital status) variables. Findings are mixed regarding the relationship between workaholism and affectively laden variables, which speaks to the complex nature of workaholism. Results also show that workaholism is related to many negative outcomes, such as burnout, job stress, work–life conflict, and decreased physical and mental health. Overall, results provide solid evidence that workaholism is best conceptualized as an addiction to work that leads to many negative individual, interpersonal, and organizational outcomes.