Good morning. CEOs depend on their CFOs more than ever. And fear them more than ever, too. Under mounting pressure from nearly every direction, many chief executives now view their closest strategic partner as a potential threat to their job security. That’s one of the key findings of the in augural BCG CEO Insomnia Index, based on a survey of roughly 500 chief executives at companies with revenues ranging from $100 million to more than $5 billion, and five years of CEO turnover data from the SP 1200. It offers a window into how CEOs assess their stress levels—and what’s keeping them up at night. More than a quarter of CEOs surveyed said their chief financial officer poses the greatest threat to their job security, ahead of every other C-suite role, followed by the COO. But the risk isn’t necessarily all about competition; it’s also about misalignment. If the CFO gets it wrong, the CEO pays the price, according to Jody Foldesy, global chief operating officer of corporate finance and strategy at Boston Consulting Group (BCG). Foldesy views the dynamic less as rivalry and more as interdependence. CEOs are relying more heavily on CFOs for decision support, making it critical that finance chiefs are central to strategy and execution. “It is critical that the CFO be deeply integrated into the development of their agenda and provide the right facts, data, and advice,” he told me. Courtesy of BCG, from the report “BCG CEO Insomnia Index.” That shift reflects how the CFO role itself is evolving. “CFOs are less backward-looking bookkeepers and much more forward-looking—developing and analyzing scenarios, providing decision support and business advisory,” Foldesy said. While many still come from accounting backgrounds, more are rotating in from FPA or business roles. As AI spending becomes a larger line item, CEOs are also looking to CFOs to lead implementation and ensure returns. “For every company’s ledger, this is becoming an increasingly large portion of spend—and if you look into the future, it’s only going to grow,” he said. But at the same time, the CFO’s regular interaction with the board, on financial performance, forecasts, and risk, can build credibility and influence, potentially positioning them as a successor. “While having a strong successor should be a part of every CEO’s legacy plan, it’s only human to feel exposed when a replacement is waiting in your own C-suite,” the report noted. The pressure on CEOs is intensifying. The report points to an average stress score of 66.7 out of 100, above the threshold typically used to indicate high stress. Growth targets and cost management rank among the top concerns, and a third say they have more to prove to their board now than they did just two quarters ago. Foldesy said managing that stress requires balance—both between short- and long-term priorities and in how CEOs approach the role in their own lives. “This is a role that can easily blot out the sun personally,” he said. “That’s why you find many CEOs experiencing the very high levels of stress the report communicates.” Have a restful weekend. Sheryl [email protected] This story was originally featured on Fortune.com ...read more read less