When you step into the lobby of 1440 Kiewit Plaza, Omaha, a security guard quickly approaches you and politely, but firmly, asks if he can help. The reason is that a few floors above are the offices of Berkshire Hathaway, the US$180 billion dollar company controlled by Warren Buffett. Without an invitation, this is as far as you will get.

With fewer than 20 employees, Berkshire Hathaway oversees investments in around 30 public companies ranging from American Express to Wesco Financial Corporation. It also has full ownership of over 60 private companies ranging from Acme Building Brands to XTRA.

Warren Buffett is acknowledged by investors around the world as the world’s greatest investor. Suppose someone had the good sense to invest $10,000 in one of Buffett’s original partnerships back in 1956 when they first started. And suppose that when the partnerships terminated in 1969, this person reinvested the proceeds in Berkshire Hathaway. Today that person would be worth over $200 million — after all taxes and expenses.

But there is much more to Warren Buffett. His integrity and no-compromise approach to government and business follies has given him an increasingly high profile in the press. Recent articles on and by Buffett include: Dividend Voodoo (Washington Post), Avoiding a Mega-Catastrophe (Fortune), The Warren Buffett You Don’t Know (Business Week) and Buffett: The Oracle of Everything (Fortune).

Warren Buffett is a friendly, talkative person who likes to explain his ideas using stories. This is the reason why over 20,000 people crowd into the annual meetings of Berkshire Hathaway in Omaha — to hear him explain his investing ideas using “down-home” yarns.

The Ability to Act Decisively is a Key Part of Buffett’s Success.

Despite this easy-going appearance, he is a person of definite action. When he comes across something of value, he acts very quickly.

For example, regularly in the annual report he invites owners of companies for sale to contact him. He lists criteria that need to be satisfied by these companies. In a recent report he ended with the preference that such businesses lie in the $5-20 billion range.

Despite the size of these purchases, for those who contact him he promises “a very fast answer—customarily within 5 minutes” as to whether he is interested. Even when he is interested, the purchase is consummated almost as quickly, generally with a simple one-on-one meeting. No lawyers, no accountants, just Warren Buffett and the owner or principal of the company being considered.

Buffett still lives in the Omaha house he purchased for $31,500 in 1958 and refuses to adopt many of the spending patterns often practiced by the very wealthy (excluding, at one point, his purchase of a corporate jet nicknamed The Indefensible).

Overall, Buffett is often described as a simple, unassuming man whose ideas about life are as interesting as his thoughts on business. He pays little attention to appearances, is passionate about his work and family, loves to play bridge, fanatically consumes Cherry Coke, hamburgers and popcorn - and just happens to be the world’s wealthiest and most successful investor.