Harvey Mackay is a businessman and columnist. Mackay is perhaps best known as the author of five business bestsellers, including Swim With the Sharks , Beware the Naked Man Who Offers You His Shirt, and Dig Your Well Before You're Thirsty. He is a nationally syndicated columnist, and one of America's most popular business speakers. He is also founder, Chairman and CEO of Mackay Envelope Corporation, whose story he tells in anecdotes sprinkled throughout his books .