As baby boomers continue to phase out of the workplace, more millennials are stepping up into leadership roles in their careers. Yet as the office culture evolves, older generations are reporting some unease when it comes to answering to younger managers.

New research from  EY, formerly Ernst & Young, finds that between 2008 and 2013, 87% of millennial, or Gen Y, managers surveyed took on some type of a management role in the workplace, and one leading challenge cited across all generations was a lack of comfort with younger employees managing older workers (72%). EY surveyed more than 1,200 cross-company professionals with responses from both managers and non-managers in the millennial generation (ages 18-32), Gen X (ages 33-48), and Baby Boomers (ages 49-67).

The amount of millennials taking on leadership roles has surged in the past five years, says Dan Black, EY Americas director of recruiting. The survey was conducted in part to find out how this impacts workplace dynamics and how companies can best engage all generations.

“This generation (Y) is large and aging,” Black says. “There is still a misconception that millennials are fresh out of school, but they have been in the workforce for some time. They’re maturing and coming of age.”

Members of Gen X were at the top of the heap when it came to positive perceptions of both characteristics and management skills, EY reports. They were cited the “best” among the generations in seven of 11 attributes including being a “revenue generator” (58%), being adaptable (49%), problem-solving (57%) and collaborative (53%).

Millennials are seen as enthusiastic (68%) but had lower scores from peers for being “team players” (45%) and hardworking (39%). And somewhat in line with their reputation, EY’s survey found that millennials were viewed by 68% of respondents as “entitled.”

Finally, boomers received high marks for being productive players for their organizations (69%) and were viewed as the hardest working of the three generations (73%). They were also reported as team players (56%) and seen as nurturing and essential for others’ development (55%).

Companies should consider workplace perks and dynamics as the millennial generation moves into the managerial track, says Black. Three-quarters of respondents who identified themselves as managers agreed that supervising across multi-generational workforces is a challenge, and 20% said they are managing a mostly-even mix of employees from all three generations.

Nearly half of the survey respondents (49%) ranked cash as their top perk, with health-care and retirement ranked first by 22%, and 18% said flexibility is most important among non-cash benefits.

“You have to be sure you are still providing the right perks,” he says. “We found that cash is still king, and that flexibility ranks as well.”

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