Meet the leaders of the Big 4, who jointly employ 1.5 million staff

• EY, Deloitte, PwC, and KPMG make up the world's largest accounting and consulting firms — known as the Big Four.
• The sector is tackling a slowdown in demand, new regulatory pressures, and the need to adapt to AI.
• These are the four leaders that have made it to the top of the firms.

EY, Deloitte, PwC, and KPMG make up the world's largest accounting and consulting firms, known as the Big Four.

They're billion-dollar companies with a collective 1.5 million staff and influence over hundreds of industries.

In recent years, the Big Four have faced a series of challenges, including a post-pandemic downturn in demand, shifting regulatory requirements, and the need to adapt their skills and services for the emerging AI future.

Two of the firms appointed new leaders in 2024. The process varies by firm but generally includes hustings, where contenders present their vision to voters, a partner vote, and global board ratification.

These are the four people who now sit at the helm of the world's biggest professional services firms.

PwC — Mohamed Kande

In July 2024, Mohamed Kande was elected as PwC's global chair for a four-year term, becoming the first Black leader of a Big Four firm.

Kande is also the first PwC head to come from the advisory division, as opposed to the audit wing.

Kande was born and raised in the West African country of Côte d'Ivoire. When he was 16, he moved to France alone to study. He worked at a PwC subsidiary called PRTM Management Consultants, before joining the firm in 2011. He became a global advisory leader in 2019.

Kande took over leading PwC's 370,000 employees at a time when it appears to be tightening pursestrings amid the consulting slowdown. Partner payouts dropped and more PwC partners took early retirement at the end of the year. In October, The Wall Street Journal reported that the firm would make its first major layoffs since 2009 and cut 1,800 jobs.

PwC is also working to rebuild trust in the Asia-Pacific region following scandals in Australia and China.

"The need for reinvention has never been more urgent," Kande said in the firm's 2024 annual review.

In 2021, he wrote a 1,000-word essay on LinkedIn about the impact his race had on his career in professional services.

"Often, I had to work hard to be included because I was different. I have felt slight but sharp jabs about my accent and my name, accompanied by quieter, larger unspokens about my skin color," Kande wrote.

"I try to give the opportunities that others gave me. I try to bring them into the room, knowing that their diversity, their unique perspective is a strength and something to be valued."

Deloitte — Joe Ucuzoglu

Joe Ucuzoglu has been Deloitte's global CEO since January 2023.

Ucuzolgu, who grew up in Los Angeles, was CEO of Deloitte US from 2019 to 2022 before ascending to the top job. He was a college intern in 1997. He rose to become a senior advisor at the SEC before rejoining Deloitte in 2015.

Deloitte is the largest of the Big Four by both revenues and number of employees with 460,000 staff.

In March 2024, Deloitte announced a major restructuring aimed at cutting costs and repositioning it for future success. It is "modernizing and simplifying" its core offering into four categories: audit and assurance, tax and legal strategy, risk and transactions, and technology and transformation.

Ucuzoglu told the firm's partners in an email that the reorganization would reduce the firm's "complexity" and "free up" more partners for client work instead of managing staff.

Under Ucuzoglu, Deloitte has taken steps to drive investment in green hydrogen, releasing a report in 2023 estimating that the energy source could become a $1.4 trillion global market by 2050 and arguing that it "is moving into prime position as a solution for hard-to-abate sectors."

The CEO continues to engage with clients. He is also a frequent speaker at the World Economic Forum, a member of the Business Roundtable, and regularly gives interviews on issues affecting the business community.

EY — Janet Truncale

Janet Truncale was elected as EY's global chair and CEO in July 2024, making her the first woman to lead a Big Four accounting firm. She joined EY as an intern in 1991.

Prior to her election, Truncale had spent almost four years as the vice chair and regional managing partner of the Americas Financial Services Organization.

The New Jersey native now heads EY's global workforce of more than 400,000 staff.

In her first public statement as global CEO, she launched a new strategy called "All in."

"All in is not just a business strategy, it captures an attitude and way of working," Truncale said. Her focus on unity comes after EY was rocked by a failed plan to break up its consultancy and audit divisions into two units, known as Project Everest.

Truncale was named as one of the "25 Most Influential Women" of 2023 by the Financial Times, which described her as "a trust builder" and "an advocate of being down to earth."

Outside EY, she serves as board chair for Women's World Banking and is on the board of UNICEF USA and the US-China Business Council.

Truncale has a BSE from the Wharton School of UPenn and an MBA from Columbia University.

KPMG — Bill Thomas

Bill Thomas became KPMG's global chairman and CEO in October 2017. Three years later, he was unanimously re-elected to a second term.

Thomas has over a decade in executive-level leadership, and was previously chairman of KPMG's Americas region between 2014 and 2017.

The Canadian leads KPMG's 275,000 employees. The firm is the smallest of the Big Four.

Over the past seven years, Thomas has focused on overseeing the development and implementation of KPMG's global strategy. Under Thomas, KPMG has launched $5 billion digital strategy investment plan.

"Over the coming years, my focus will be on continuing to enable and empower these talented teams to achieve their full potential," he said in a statement released on his reelection in 2020.

KPMG's global annual revenues have grown by 45% since the year Thomas was appointed CEO. In its latest annual earnings, it reported annual revenue of $38.4 billion.

Thomas stays largely out of the media spotlight, giving few interviews. Before entering the business world, he studied science, which he says is "extremely relevant today as technology infuses every part of our business and the businesses of clients."

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