• Matthias Müller. Picture: BLOOMBERG/KRISZTIAN BOCSI

  • Yahoo CEO Marissa Mayer. Picture: REUTERS

  • Carlos Brito. Picture: BLOOMBERG/ANDREW HARRER

Carlos Brito

The Brazilian-born head of the world’s largest brewer faces a host of challenges. To complete the roughly $108bn takeover of SABMiller in the second half of the year, as planned, he must secure regulatory approval in South Africa, Europe and the US. He also must integrate the companies and cut $1.4bn in costs. And he must do so while navigating challenges in AB InBev’s biggest markets: Brazil, which is in recession, and the US, where beer-sales volumes are contracting.

Marcelo Claure

When Mr Claure took over as CEO of Sprint in 2014, the carrier had been losing customers and money for several years. Last year, he was able to clock a modest return to subscriber growth. But ahead of a big debt maturity in 2016, the pressure is on for him to cut costs while continuing to add new subscribers. If not, some analysts say Sprint could run out of money.

Steve Easterbrook

In less than a year of running McDonald’s, Mr Easterbrook has tried some bold moves to try to turn around the struggling burger chain. He introduced all-day breakfast, simplified the menu, and vowed to curb the use of antibiotics in chicken and switch to cage-free eggs. Initial signs are positive, but investors and customers are waiting to see what else he has in store to maintain the world’s biggest fast-food chain’s turnaround in 2016.

Steve Ells

After years of bemoaning the ills of fast food and creating an avid following for Chipotle Mexican Grill, founder Mr Ells is in the unusual spot of playing defence. The co-CEO of the burrito chain apologised in December for foodborne-disease outbreaks that sickened customers in several states and added to other business challenges for Chipotle. In 2016 he will have to win back consumer trust and convince people that Chipotle’s food is safe.

Hunter Harrison

Mr Harrison faces his biggest challenge yet at the helm of Canadian Pacific (CP) Railway — completing his $30bn hostile bid for Norfolk Southern. The railroad executive and activist investor and CP shareholder William Ackman are betting the deal will boost the combined companies’ profits and improve service for shippers. Norfolk Southern’s board opposes the offer as too low and argues that regulatory rejection of the tie-up is likely amid industry concerns that the deal would trigger further consolidation and reduce competition.

Andrew Liveris

The chief executive of Dow Chemical is on the cusp of pulling together a long-pursued combination with rival DuPont. The companies agreed to form an agricultural and chemical giant worth $120bn, with Mr Liveris as executive chairman of the board before the combined entity eventually splits into three smaller companies. Not everyone wants him to stick around. Activist shareholder Daniel Loeb, who has been sharply critical of Dow’s strategy, has called for Mr Liveris, 61 years old, to be removed. And the combination is likely to face a detailed, lengthy review by antitrust regulators.

Marissa Mayer

Forget turning around Yahoo, Ms Mayer will probably spend 2016 trying to keep her job and resolve the imminent crisis gripping the 20-year-old internet company. Investor confidence in the CEO dropped in December, when she shelved a plan to spin off Yahoo’s valuable stake in Alibaba because of potential tax risks. With revenue declining and executives fleeing, some investors are calling for a sale of the internet business.

Sheri McCoy

In December, Ms McCoy agreed to sell a stake in Avon Products to Cerberus Capital Management and carve out the beauty company’s money-losing North American business. The bold move is aimed at reviving Avon’s fortunes, but also puts the 57-year-old’s job at risk because the company is replacing half its board of directors. As she nears her fourth anniversary as CEO, investors are becoming impatient for Avon to show sustained sales growth.

Matthias Müller

Mr Müller was catapulted into the driver’s seat at Volkswagen, Europe’s biggest car maker, in September in the wake of a damaging emissions-cheating scandal. A company veteran, he is now steering Volkswagen’s fortunes through its worst crisis in its nearly 80-year history. Volkswagen could face billions in fines and compensation charges. Mr Müller’s challenge in 2016: minimise the regulatory fallout and financial outlay from the scandal, keep VW profit on track, and restore confidence in the brand.

Oscar Munoz

Mr Munoz faces a daunting comeback in 2016 when he returns to helm United Continental Holdings following an October heart attack that put him on medical leave just weeks after he became CEO. Mr Munoz was an airline neophyte before his September appointment, and is scheduled to return in the first quarter. He will have to resume his efforts to fix the deep labour and operations problems that have plagued United for years, along with rebuilding a depleted management bench.

Doug Oberhelman

After becoming CEO of Caterpillar in 2010, Mr Oberhelman raced to open plants and make acquisitions to meet demand for construction and mining equipment. Then a crash in commodity prices and an abrupt slowdown in China left Caterpillar with excess capacity. It faces a fourth consecutive year of falling sales, assuming forecasts for a dismal 2016 prove accurate, piling further pressure on him.

Michael Pearson

Mr Pearson has taken medical leave from Valeant Pharmaceuticals International, which disclosed that the CEO is battling severe pneumonia. The Canadian drug company has been struggling to overcome regulatory and strategic challenges. This was not what Mr Pearson had in mind when he left McKinsey as a consultant in 2008, seeking to remake Valeant through acquisitions, and research and development cutbacks. The company now faces probes about its drug pricing and other practices, and the length of Mr Pearson’s absence remains an open question.

Ginni Rometty

After 14 straight quarters of declining revenue, International Business Machines (IBM) is trying to reinvent itself for the second time in a quarter century. CEO Virginia "Ginni" Rometty has charted a course for the emerging realms of cloud computing, big data and artificial intelligence. Her challenge is to shift IBM’s business from projects tailored to large, individual customers to offerings that appeal to entire industries; for instance, services that use weather data to help retailers manage inventory. If she cannot show results in 2016, shareholders’ patience may run out.

David Taylor

Procter & Gamble’s third CEO since 2013, Mr Taylor has been tasked with leading the maker of Pampers diapers, Pantene shampoo and Gillette razors out of a protracted sales slump. The P&G veteran is under pressure to show broad-based sales growth and turn around struggling brands like Olay. He will have to complete an overhaul that has so far shed dozens of brands, while sharing duties with his predecessor who has stayed on as executive chairman.

Meg Whitman

The new year raises the curtain on Meg Whitman’s second act. In Act I, she divided in two Hewlett-Packard, the moribund Silicon Valley pioneer she took over in 2011. Now, as CEO of the new Hewlett Packard Enterprise (HPE) — the former company’s corporate-computing half — she must focus on growth. Cloud computing has brought a sea change in corporate buying habits. Ms Whitman’s HPE will try to help its customers bridge the gap between their own data centres and cloud services sold by companies such as Amazon.com and Microsoft.

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