Audiences from each participating country vote, after which a spokesperson from each of the 37 nations presents the points awarded (the UK's will be presented by Catherine Tate). The most any country can award another is 12, and the least is the dreaded 'nil pwa'.
But that's just the beginning. Once we have these votes, votes cast by telephone from each participating country – and for the first time, viewers in the rest of the world – are totted up, providing one overarching score for each song. This can change everything, so it could well go down to the wire.