Recent scholars (Twenge & Campbell, 2009) have documented a continuing trend, generation by generation, of increasing levels of narcissism in the American population. This ongoing trend has often been associated with the millennial generation, who, on average, register increased levels of subclinical narcissism when compared with previous generations. Higher narcissism levels come with important implications for the classroom and workplace. In this study, we argued that one relevant concern would be teamwork skills. We argued that individuals higher on narcissism, and particularly those high on the subdimensions of entitlement and superiority, would be overconfident and would acquire fewer behavioral skills in a behaviorally based learning environment. We found some evidence to support these concerns and discussed our study and its implications for scholars, managers, and educators. We close with a call to readers to not conflate the millennial generation with narcissism generally, nor to overreact to the documented rise in narcissism levels, but to focus on its most problematic aspects in individual students and employees who demonstrate these attributes.