Industrial-Organizational psychology has witnessed an increased attention in maladaptive personality traits, particularly narcissism A vast and growing body of research has demonstrated the negative consequences of narcissism at work, for instance in relation to abusive supervision or counterproductive work behaviors While this has led to an accumulation of knowledge on the effects of narcissism at work, the exclusive focus on predictive effects is at odds with recent evolutions in the literature to conceptualize personality traits more from a dynamic perspective and to consider their antecedents as well as their consequences With the present proposal, we respond to the call for a developmental approach to narcissistic personality by studying how this trait changes throughout adulthood and how it develops in relation to specific professional experiences We propose a series of studies to investigate (a) the extent to which narcissism has dynamic qualities throughout adulthood and (b) which kind of occupational characteristics and experiences at work have the potential to either enhance or diminish narcissism in individuals By studying not only the outcomes but also the antecedents of narcissism at work, this project offers a new and much-needed developmental perspective on the role that narcissism plays in people’ professional roles