Kohlberg Kravis Roberts & Co (commonly referred to as KKR) is a New York City-based private equity firm that focuses primarily on late-stage leveraged buyouts. It was founded in 1976 by Jerome Kohlberg, Jr., and cousins Henry Kravis and George R. Roberts, all of whom had previously worked together at Bear Stearns.

The KKR approach
After the 1987 resignation of Jerome Kohlberg at age 61 (he later founded his own private equity firm, Kohlberg & Co.), Henry Kravis succeeded him as senior partner. Under Kravis and Roberts, the firm was responsible for the 1988 leveraged buyout of RJR Nabisco. At a cost of $31.4 billion including net debt of $6.3 billion, it was then the highest price ever paid for a commercial enterprise, financed with a combination of bank debt, high yield bonds, and a $3.6 billion equity investment by KKR. The deal was only rivaled in July 2006 by the $33 billion buyout of U.S. hospital operator Hospital Corporation of America, in which KKR also participated, though the RJR deal was larger, adjusted for inflation.
The publicity surrounding the RJR Nabisco buyout led to a book, Barbarians at the Gate: The Fall of RJR Nabisco and subsequent film. The initial equity injection by KKR was $1.5bn, in July 1990 they were forced to put in an additional $1.7 bn.
The RJR transaction benefited many of the parties involved. Investment bankers and lawyers who advised KKR walked away with over $1 billion in fees, and Henry Kravis and George Roberts attracted unprecedented amount of publicity that turned the cousins into instant celebrities.
However, KKR's investors, mainly public and private pension funds who provided KKR with the capital for this buyout, did not do so well. After over fifteen years of efforts that included taking RJR public, as well as exchanging shares of RJR for the ownership of Borden Foods, formerly chemicals-to-pasta conglomerate, KKR finally exited the investment in 2005, selling the remnants of its stake in Borden's Chemical division to Apollo group at a significant loss.
In the recent years, KKR's track record has been mixed. Heavy losses on such investments as Regal Entertainment Group, Spalding, and Primedia were offset by successes in Willis Group, Wise Foods, Inc., Shoppers Drug Mart, Bell Canada Yellow Pages, Wincor Nixdorf, MTU Aero Engines and TXU, among others. KKR opened a successful office in London led by Johannes Huth, but it lost many of its original partners, including Saul Fox, Ted Ammon, Ned Gilhuly, Mike Tokarz and Scott Stuart who were instrumental in establishing KKR's reputation and track record in the 1980s. KKR remains tightly controlled by Kravis and Roberts. The issue of succession will likely continue to leave a large dark cloud over KKR's future.

Deals
(may 2006 : consortium to buy Nielsen (former VNU) ) (nov 2006 : buys French Yellow Pages)

On May 28, 2007, KKR announced it had withdrawn along with CVC from the consortium bidding for Australian retailer Coles Group. Recent activities
As of 1996, general partners (as opposed to associates) included Henry Kravis, George R. Roberts, Paul E. Raether, Robert I. MacDonnell, Michael W. Michelson, Saul A. Fox, James H. Greene, Jr., Michael T. Tokarz, Clifton S. Robbins, Scott M. Stuart, Perry Golkin and Edward A. Gilhuly. Gilhuly was the Managing Partner of KKR's European operations, based in London until November 2004, when he returned back to the United States. Johannes Huth, then a 44 year old (now 46) German national, was appointed head of the London office. Along with these partners and employees is one of the investors and share owner, Robert Rosner.