Charlie and I believe that a CEO must not delegate risk control. It’s simply too important. At Berkshire, I both initiate and monitor every derivatives contract on our books… If Berkshire ever gets in trouble, it will be my fault. It will not be because of misjudgments made by a Risk Committee or Chief Risk Officer.

Warren Buffett, in his letter to shareholders for 2009: http://www.berkshirehathaway.com/letters/2009ltr.pdf