From brats to bosses—Gen Y to dominate by 2025

With millennials set to comprise 75 percent of the global workforce by 2025, there could be challenging times ahead for business leaders, according to a Deloitte study on the attitudes and expectations of generation-Y employees.

Millennials want to work for organizations that foster innovative thinking, develop their skills and make a positive contribution to society, the study, released on Tuesday revealed.

(Read more: This is how fast China's workforce is shrinking)

At the moment, only about half of millennials feel the organization they work for encourages employees to suggest new ways of doing things or rewards them for innovative ideas.

More than 7,800 individuals – born in 1983 or later, holding a college degree and in full-time employment – across 28 countries were surveyed by the management consulting firm.

Tomaz Levstek | E+ | Getty Images

"It is clear that millennials want to innovate and businesses should be listening," said Barry Salzberg, CEO of Deloitte.

"Fostering a culture of innovation will not only help retain high-performing talent but it will also drive growth by creating opportunities for individuals to unlock the next game-changing innovations," Salzberg said.

(Read more: Britain's workforce: Aboutto be transformed?)

Another source of discontent among gen-Y employees is the lack of attention paid by companies to nurture their future leaders.

Roughly 50 percent of those surveyed agreed their organization does all it can to develop their leadership skills, while this figure was less than 40 percent in France, Spain, South Korea, and Japan.

"Businesses that fail to address these concerns may find they will lose skilled professionals in the years ahead, as many of the most talented members of the millennial generation decide to leave large organizations and instead work for themselves," Deloitte said in a report.

(Read more: Money worries keep Gen Y from buying, leasing cars)

Around 70 percent of those interviewed see themselves working independently at some point, rather than being employed within a traditional organizational structure.

While 52 percent of millennials in developed markets expect to eventually work independently, the danger of losing talent is even greater in emerging markets, where the figure rises to 82 percent.

"Although millennials value its role in creating jobs and expanding prosperity, they have larger ambitions for business. [They] see a large gap between the potential of business to address the challenges facing society and the actual impact it is having," Deloitte said.

(Read more: Gen Y managers perceived as entitled, need polish)

"Fulfilling this potential will require businesses to do a better job of encouraging new thinking within their own organizations to develop innovative products and services, while also working collaboratively with government, with nonprofit organizations, and with other companies to develop creative solutions. The stakes are high," the company added.

—By CNBC's Ansuya Harjani. Follow her on Twitter:@Ansuya_H