Today's issue of PR influences covers 'greenwashing' - "the act of misleading consumers regarding the environmental practices of a company or the environmental benefits of a product or service."

It's good to see professional PR folk in action. Part of their job is to make sure that companies don't get carried away with their rhetoric and make fools of themselves. Of course, there will always be poor PR folk who see their job as "putting lipstick on the pig". We have to take a certain amount of personal responsibility for filtering good PR from bad.

Once upon a time, it was easy to pull the wool over most people's eyes, by writing good press releases, advertisements and brochures. The public didn't have much of a voice - the letters page of the newspapers, the complaints desk of a company or the local advertising standards authority. In other words, except in newsworthy cases, not a lot would happen.

Now, with bloggers galore, some will always be expert enough to see through the greenwash and blow the whistle. And we all know how fast bad news travels through the blogosphere. And how mainstream media organisations quickly pick up good stories.

We hear about companies that claim to be carbon neutral which is wonderful, if true. But, if close examination were to reveal that one of the directors drives a gas guzzler or that the heat from the data centre is being vented to the atmosphere, then the carbon neutral claim falls apart and the company risks ridicule.

The best option is transparency. To show what steps are being taken to run a sustainable (financially and socially, as well as environmentally) business and not make any pretence that things are better than they are. Some IT companies - IBM, Sun, Hewlett Packard, Cisco and Fujitsu Siemens spring to mind immediately - seem to be very forthright in their claims and their explanations.

They still fly people around when necessary, but they'll talk about how much travel has been cut. They still have to run high-powered data centres - even more so for those who offer hosted software services, but they'll talk about how much they've slashed their energy bills through consolidation, virtualisation and other measures.

Of course, they would all like to sell more equipment, software and services and they will dangle the cost and environmental savings that are possible. But they are also well aware that new equipment brings its own environmental costs, including the disposal of old equipment. Honest discussion around these issues will win vendors more customer loyalty than misleading claims based on dodgy premises.

Indeed, they may well find that their revenues rise for hosted services, consulting and software, even if an increasing awareness of sustainability among customers were to lead to a slowdown in hardware sales.