I had two interviews and a written test at Cambridge. From what I can remember, written test was a few logic questions, then we had to summarise an article from the economist in about 200 words.

The first interview was done by two economists. They asked "why do you want to do economics?", then there was a game theory question where we had to work out what our strategy would be in a two stage game against a computer. Then they asked "Is there an economic issue in the news recently that you've found particularly interesting?" - I said George Bush's proposed tax cuts - and we spent most of the rest of the interview discussing that. They asked things like "what would be the effects of the US tax cuts on the uk? Explain why". Also, "Which parts of the Cambridge course do you think you'd particularly enjoy?"