Thanks to the dot.com crash, it is easy to be cynical about alliances. Professor Ben Gomes-Casseres admits: "Yes, things went to an extreme with alliances, as in every aspect of business.  People were forming 20 alliances to put the logos on their website so they could raise venture capital.

Also we saw a lot of alliances struck which simply couldn't work - remember Microsoft and AOL or Microsoft and Sun over Java?"

He accepts that the crash means far fewer new alliances are being formed, but says that this reflects lack of business confidence, not the failure of the alliance model.

"Alliances are an attacking, entrepreneurial way of staking out new ground. So, naturally, we don't see so many today."

"Companies like Cisco and others are consciously building a portfolio of alliances."

Gomes-Casseres reckons that the last ten years has seen a step change in how companies handle and manage alliances: "They have gone from being a peripheral tool to a centrepiece of corporate strategy.

Companies like Cisco and others are consciously building a portfolio of alliances - in much the same way that an investor builds an investment portfolio.  And the alliance portfolio fills the same role - spreading risk and maximising opportunity."

At the same time, the art of alliances is being gradually turned into something approaching a business science.  "People are coming up with new and more precise ways of measuring alliance success.  Companies like Eli Lilly are establishing whole departments dedicated to building alliances."

The new professionalism shows itself in the way alliance managers are communicating and discussing the best way forward and the subject is becoming an academic discipline in its own right.  In the same way that some individuals become emotionally literate, so some companies are becoming alliance literate.

He reckons the main secret to success is to move away from seeing an alliance as an end in itself, to seeing it as something which serves well thought-out strategic goals: "Too few companies follow the approach adopted by Corning.

"That very late 90s notion of co-opetition has been discredited."

It decided to concentrate on its core glass-making skills, but to attack big vertical markets by forming alliances in areas like optical fibre, TV screens, etc.  There was a clear strategic rationale behind its alliance programme.  This has to be in place if alliances are to work."