Project Management is big business. Qualified and experienced consultants can rake in thousands of pounds per day, by speeding through business changes that might otherwise take much longer to implement. But often there's a price to pay, over and above the consultancy fee.

Having been involved in various projects over the years, the most apparent problem to me is that some Project Managers, nice though they often are, suffer from an over-simplification of other people's roles. To put it another way, and to paraphrase the pointy-haired boss in the Dilbert comic strip, "Everything that I don't understand must be easy."

This leads to a massive underestimate of both the time involved for a particular task and the competence of the person responsible for that task. It's an error that could easily be avoided by actually listening to the people concerned and not automatically dividing their time estimates by a factor of three "because they're obviously lazy."

Another problem is that the people who employ Project Managers tend to assume that everything is a project, and that any Project Manager can therefore handle any project. Obviously the Project Manager isn't going to disabuse the prospective client of this notion, but the truth is rather different. I've seen what happens when you hire a Project Manager with no Internet experience to implement a new Web site, for example. It's not pretty. The learning curve is too steep to climb.

About halfway through such a project, aware that things aren't going entirely to plan, the Project Manager will try to reassert his or her authority by muscling in on the people involved, chasing them for regular "Red, Amber, Green" status updates (which take up more time and slow the project down even further), scheduling "progress" meetings (in an attempt to spread the blame more widely) and telling everyone how to do their jobs.

To the Project Manager this is all perfectly normal. To everyone else it's an effective way of destroying all motivation, by taking away any chance of creating something outstanding and placing more obstacles in the way of efficient working practices.

Add a mix of arbitrary, impossibly tight deadlines that don't change even when new delays crop up, then sprinkle in a few major, unforeseen problems that only surface towards the end of the project, and you have a recipe for stress and misery.

Not that the Project Manager will be aware of this trail of destruction. By now he or she will have sidled into a completely new project, leaving behind a shell-shocked team to pick up the pieces or, more likely, quietly sweep the whole sorry affair under the carpet and start looking for new jobs in a more enlightened organisation.

Business managers beware: just because it says PRINCE II on the CV doesn't mean that the consultant has a clue about the requirements of your particular project. Stop and think for a moment. You probably already have all the resources you need in-house. Save time, money and staff churn by making better use of them before you think of bringing in someone from outside.