Business publications and the popular press have stressed the importance of creating conditions for meaningful employee expression in work roles, also known as engagement. Few empirical studies, however, have examined how individual or situational factors relate to engagement. Consequently, this study examines the interplay between employee age, perceived coworker age composition, and satisfaction with older (older than 55) and younger (younger than 40) coworkers on engagement using a sample of 901 individuals employed in the United Kingdom. Results indicated that satisfaction with one's coworkers related significantly to engagement. Moreover, perceived age similarity was associated with higher levels of engagement among older workers when they were highly satisfied with their coworkers over 55 and lower levels of engagement when they were not.Keywords: age, diversity, engagement, similarity, satisfaction with coworkers Two seemingly unrelated workplace trends could have a considerable conjunctive impact on management. First, the global workforce is aging. In the United States, there are 18.4 million workers age 55 or older, a figure representing 13% of the workforce. By 2015, this number is projected to grow to 31.9 million, or approximately one in every five employees (U.S. General Accounting Office, 2001). Similarly, 41% of the Canadian working population is expected to be between the ages of 45 and 64 by the year 2021 (cf. Lende, 2005). In the United Kingdom, 30% of workers are over 50 (Dixon, 2003). Across the European Union as a whole, the proportion of workers over 50 is expected to rise nearly 25% over the next 15 years ("Turning boomers into boomerangs," 2006).Simultaneously, the challenge of engaging employees is mounting (Fleming, Coffman, & Harter, 2005;May, Gilson, & Harter, 2004;Pech & Slade, 2006). Kahn (1990) initially defined engagement as "the harnessing of organization members' selves to their work roles" (p. 694). Despite its seeming conceptual overlap with existing constructs such as organizational commitment and job involvement, evidence suggests that engagement is a distinct construct (Hallberg & Schaufeli, 2006). According to a survey of 656 chief executive officers hailing from countries around the world, engaging employees is the fourth most important management challenge, behind creating customer loyalty, managing mergers and alliances, and reducing costs (Wah, 1999). Further illustrating the magnitude of this challenge, the Gallup Organization recently found that nearly 20% of U.S. employees were disengaged and an additional 54% were effectively neutral about their work (see Fleming et al., 2005). The authors estimated disengaged employees to cost U.S. organizations more than $300 billion per year in lost productivity. Furthermore, research by Gallup and Towers Perrin (Momal, 2003;Seijts & Crim, 2006) suggests that employee disengagement is equally problematic in other countries as well. In fact, the latter found that only 14% of more than 85,000 employees across 16 countries were eng...