Azeem is spot on about what UK startups face, but here's a couple more overriding themes that I've observed:<p>- There's a culture of "what's in it for me?", so it's hard to get advisors or put together an advisory board without getting out your cheque book.  People in the valley (outwardly) seem to be more willing to take a chance, and trust that they'll get looked after in the event the business goes well.  Not as much altruism in London.<p>- The UK is more risk-averse than the valley, you don't just need a vision, a prototype and a quality team, you need all that plus traction and profit before you fall inside investors appetite for risk.