Mr Mandelson discovered them on a recent trip to Silicon Valley in California, but actually we've had quite a few of our own here in Britain for some years - Silicon Glen, the M4 corridor and the Cambridge Science Park to name a few.
For Mr Mandelson, however, it's all new and very exciting. Experts in clusterology have been summoned to tell him more about the phenomenon, while Scottish Enterprise has even appointed its very own "head of clusters".
The idea that like-minded companies in related industries might prosper more by grouping themselves together, sharing suppliers and ideas and drawing from the same knowledge pool sounds more like common sense than anything else, but it's also very Third Wayish.
Every minister parachuted into the DTI has to have his, or her Big Idea and clustering looks ominously as if it could be Mr Mandelson's. His immediate predecessor, Margaret Beckett, was moved from the job before she could really develop one. The Three Pillars of strong markets, modern companies and an enterprising nation, don't really count. But her predecessor, Michael Heseltine, made up for it. He had three Big Ideas - benchmarking, national champions and his great bonfire of red tape.
Actually, the only big idea from Victoria Street that has stood the test of time is privatisation, which was Sir Keith Joseph's contribution to society. Mr Mandelson could have kept the legacy alive, but he has reportedly ditched the option of privatising the Post Office to pursue his own agenda. Just who's going to remember clustering in thirty years time is an interesting question.Reuse content