Kevin Turner is to leave Microsoft to become CEO at financial services company Citadel Securities.
Turner was appointed chief operating officer of Microsoft in 2005, three years after the departure of previous incumbent Rick Belluzo.
Prior to joining Microsoft, Turner held various positions at retailer Wal-Mart, including CIO for Wal-Mart Stores, where he worked his way up from the bottom. Turner joined the retailer as a cashier while studying for his undergraduate degree.
Turner was responsible for the strategic and operational leadership of Microsoft's worldwide sales, including the firm's field marketing and services organisation. He managed support and partner channels and corporate support functions - including Microsoft's own IT - as well as licensing, pricing and operations.
Latterly, Turner was responsible for the sales and marketing drive behind Office 365 and Microsoft's Azure cloud. More than 51,000 employees across 191 countries ultimately reported to Turner.
Turner masterminded Microsoft's entry into retail stores in 2009, and served on the Senior Leadership Team, the internal body that sets Microsoft's overall strategy and direction. He was an outside candidate to replace Steve Ballmer when he stepped down as CEO of Microsoft 2013.
Ballmer was the target of internal anger over the way in which scorecarding turned employees and their teams on each other, but it was Turner who introduced the concept to the company. Turner also promoted the use of scorecarding to rank employees while at Wal-Mart.
However, as in 2002, Microsoft is not planning a direct, like-for-like replacement for Turner. Instead, the company will disperse his responsibilities across a number of senior managers and executives.
Turner will stay on at Microsoft until the end of the month, according to an internal email sent by CEO Satya Nadella.
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