Being a CEO is said to be a lonely job, but it helps when you can count investing oracle Warren Buffett as a trusted adviser. 

That was the summation of American Express (ticker: AXP) Chief Executive Stephen Squeri, who recently sat down with Barron’s Andy Serwer. Buffett’s Berkshire Hathaway (BRK.A) is American Express’ largest shareholder, holding about 20% of its shares, according to FactSet data.

Source: finance.yahoo.com