DaVita, the Denver-based provider of kidney care services with $6.1 billion in 2009 revenue, named Luis Borgen CFO. He succeeds Rich Whitney, who is leaving the company. Borgen, 39, is joining DaVita from Staples, where he most recently served as senior vice president of finance for the U.S. retail division. In his 12 years at Staples, Borgen also worked as vice president of corporate finance and analysis and in treasury. Before joining Staples, he served for five years in the U.S. Air Force.

John Howard joins AllianceBernstein, the $3.5 billion investment management firm, as CFO and senior vice president. He succeeds Robert Joseph Jr., the New York-based firm's CFO since 1994, who is retiring at the end of the year. Howard, 40, most recently served as CFO and chief operating officer of AQR Capital Management. Before joining AQR in 2007, he spent almost a decade at Knight Capital Group, including as its CFO from 2003 to 2007.

Bank of the West, a San Francisco-based financial institution with $60 billion in assets and $3.5 billion in revenue, has appointed Duke Dayal CFO. He succeeds John Wojcik, who retired last fall after 18 years with the bank. Dayal, 45, joins Bank of the West from private equity firm Brysam Global Partners, where he was a managing director. Earlier, he worked for Citibank, where his positions included CFO of Citibank West, and Diageo, where he worked in finance.