In 2009 David Cameron showed the potential to be a good leader. How is he faring now that he's in office?

I first assessed Gordon Brown's leadership qualities for Director shortly after he became prime minister in 2007. In January 2009, I looked again at how he had performed so far, and this time assessed the potential of David Cameron and the other main party leaders. The verdict in 2009 (as it had been in 2007) was that Brown would be a disaster, but Cameron and Clegg showed the potential to be good leaders. We have now got what we asked for. So, with Cameron having been in office—albeit in coalition with Clegg—since May, it seems to make sense to have a look at how he is shaping up as a leader.

All along we have tested leaders against five criteria: vision, ability to motivate others, decisiveness, ability in a crisis and trustworthiness. Back in 2009, as leader of the opposition, Cameron scored well on vision, his ability to motivate and trustworthiness. But having lacked authority at the start of the credit crisis and recession, he scored less well for his decisiveness and particularly his ability to handle a crisis.

The overall summary then was that if he could convert words into action he could prove to be a very good leader. So how is he faring in these categories now?

Vision. David Cameron is in danger of being seen to have just one vision—that of balancing the government's books. But being a diligent accountant is presumably not what he has in mind as his legacy and doesn't inspire people. Clearly, there is more to his vision than cuts. He talks about the Big Society, but even his civil servants do not know exactly what this means. And a vision that is not understood by those charged with implementing it does not count.

Ability to motivate others. His work in building an unlikely coalition with the Liberal Democrats—and with Nick Clegg in particular—and keeping it together so far, earns Cameron nearly full marks for his motivational ability. Whether he can motivate the broader population to accept some very unpopular decisions will be perhaps one of the biggest tests of his leadership.

Decisiveness. To his credit, Cameron has used his honeymoon to push through educational and health reforms fast. Other departments will follow. You may like or dislike the changes, but they show we have a prime minister who is not afraid to make decisions. Blair's autobiography is full of regret over not making the bold decisions early on that were required.

Good in a crisis. So far, Cameron has not had a fully fledged crisis to deal with. Partly for personal reasons, he has maitained a strangely low profile this summer as a number of minor crises have swirled around his party. Cameron needs a major crisis, preferably not of his own party's making, to establish his true leadership credentials.

Trustworthiness. No politician was honest during the election about the scale of cuts needed and the pain this would mean for everyone. But since May, Cameron has been brutally honest about the difficulties we face. He needs to keep going with this. Every leader must be trusted, even if he is not liked. Cameron may not be liked, but if we trust him he can survive.

Overall, Cameron is doing well. He is certainly an improvement on the last tenant of number 10. He needs to work on his vision, and on communicating it. And he needs a good crisis.