"Collaborations have been born out of a recognition we've made that, although sports is our foundation, our interaction with customers doesn't need to stop at the playfield," explains Neil Beeson, general manager of Puma's sport fashion division, a team set up to address this growing market. "And it's born out of a realization that design is at the heart of what we do," he continues. "Alternative types of collaborators, bring different perspectives to your business."

In March 2005, Puma, one of the pioneers of "sport fashion," announced it had taken brand collaboration one-step further by opening its first multi-branded store. The store houses its collaborations with Philippe Starck, Neil Barrett and Christy Turlington all under one roof. Sited among the hip hotels, boutiques and bars of New York's fashionable meatpacking district, the store adheres to one of the key motives behind co-branding: to root the brand in credibility among fashion-savvy shoppers. Ever since Run DMC sang the ode to low-cut sneakers "My adidas," brand owners have recognized that if their brand is seized upon by the in-crowd, their influence will radiate out to the high street.

The multi-branded store enables a large brand like Puma to re-connect with its customers and get personal. It's a U-turn from the biggest-is-best ethos of retail temples pioneered by Nike (which opened its first Nike Town in 1990). This new kind of retail experience positions Puma as a brand nurturing rather than monopolizing innovation. "When you travel abroad you find that one concept store looks the same as another," continues Beeson. "But our model isn't too dissimilar to that of a boutique. A boutique owner presents his own view of the world and becomes a sort of designer in his or her own right. It's the same with the multi-branded store, except we control the access point ourselves."

Which bring us to a further key motive behind brand collaborations: the ability to "crossover" a brand into new markets and attain instant credibility. While many brands still shy away from co-branding as a route to growth, collaborations afford a brand an opportunity to tentatively chance its toe in the water and innovate. This can potentially remove some of the risks associated with leaping head first into brand and line extensions.

That's not to say that brand collaborations aren't without their risks. In January 2005, Pharrell Williams, the musician and designer behind Bathing Ape, fell out with Reebok over its Billionaire Boys Club (BBC) collaborations and threatened to sue for US$ 4 million dollars.

According to media reports at the time, Williams said, "Reebok could not adequately produce the full range of licensed products in a manner consistent with the design and quality standards and specifications required by BBC."

The legal wrangling was quickly smoothed over out of court, but Matt Hirst, youth trend consultant at Headlight Vision argues that the Reebok case stressed an important lesson for large brands poised to enter into brand partnerships. "To be credible, it's massively important that the collaboration holds up, which means that the bigger brand needs to cede control over to the collaborator," he argued. "Reebok just hadn't given full support to the artist. It shows just how wrong it can go."

Rob Mitchell advises brands how to use language and express their tone of voice for The Writer in London.