What a great question! We have some things to learn from the ancients when it comes to this question. The Greek had an uncanny ability to network and so their trade was truly international even in the ancient world.
I think more companies now are realizing the importance of strategic alliances and networking. We are actually seeing more and more companies with this business model. Let me give you some examples. Target, the massive chain store, works with many different designers to promote them, but in return the Target brand gets out there. J. Crew the clothing store also has alliances with many smaller, but good quality companies, such as Mackintosh coats. We also also seeing this other companies such as Jack Spade and to a lesser degree Apple Computers. The idea here is that teamwork can benefit many companies, not just one.
Thanks for your answer. It has open my eyes to broaden my upcoming small business.