In some companies it plays a key part in strategy. Paul Myners as chairman of Land Securities wrote in the property company's recent annual report: 'We want to be a provider of choice and our track record plays a vital role. It is quite simple: we want to be the sort of company people prefer to do business with.'
This is a good starting point. The core of reputation is that the people out there - media, customers, suppliers and voters - know what the company is about. They need to see a clarity of purpose in the business and a clarity of image.
But reputation also requires trust, which involves consistent delivery. The more reliable the company is and the more it keeps its promises, the more it builds.
Perhaps the key point is that reputation has to be integral to the business and its values. In a way it is not something to be managed, it is something to be lived.
But this is where it gets interesting. Those values may not be things most people are comfortable with. It is easy to understand how BMW keeps its reputation for engineering and design excellence, and it is easy to see how Marks & Spencer under Sir Stewart Rose regained its reputation for quality and value.
Tesco has a reputation for being aggressive and sometimes ruthless towards everyone from suppliers to local planning authorities, but manages to maintain its overall reputation by creating the understanding that it is doing this for the benefit of its customers.
And what about Ryanair, where chief executive Michael O'Leary goes out of his way to lower expectations? This too is smart. His proposition is cheap travel, not that passengers will be pampered. Ryanair does not put its reputation at risk by promising what it cannot, or will not deliver. But so many other companies do, and pay the price.
Anthony Hilton is City commentator on London's Evening Standard