The United States is more successful than the United Kingdom when it comes attracting top scientists.
The Royal Society Census 2000 adds weight to the decision announced last week to set up a Pounds 4 million-a-year scheme to attract 50 world-class scientists.
It revealed that the proportion of fellows of the Royal Society who are based in the US is far higher than the percentage of members of its American equivalent, the National Academy of Sciences, based in the UK - 12 per cent (144) compared with 0.2 per cent (4).
Sir Eric Ash, treasurer and vice-president of the Royal Society, said the UK had to compete in a global recruitment market to get the best brains.
"If the UK can engage in this competition with enough vigour, it is entirely possible that we could achieve a brain gain," he said.