Isabelle Kocher

A former French civil servant with multiple degrees in physics, Kocher heads French energy giant Engie, and is the only woman on the CAC 40, France’s index of the top 40 companies by market capitalizations. Since her tenure began in 2016, she has pushed the company to reduce its reliance on fossil fuels in favor of renewable energy, and this year, she has made efforts to streamline the business, saying it would pull out of 20 markets.

But her efforts have also received a mixed reception from investors who have been waiting for that shift to pay off. In 2018, Engie—No. 126 on the 2019 Fortune Global 500—saw its revenue drop 1.5%, while profits dropped 24%.

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