No one wants to strangle a fast-expanding young industry with regulations. The internet illustrates the benefits of allowing an exciting new technology to explode in a virtually unregulated environment. But some promising new fields are likely to grow better inside a well-constructed regulatory framework, either because they are exceptionally sensitive in moral and ethical terms or because they pose a potential hazard to health and the environment.

Nanotechnology comes clearly into the latter category. The UK government, perhaps sensitised by its unfortunate experience with genetically modified crops, recognised this commendably early. In 2003 it asked the Royal Society and the Royal Academy of Engineering to look into the environmental, safety, ethical and social implications of nanotechnology - and last year the academies released an excellent report, calling for tighter regulations and more research into the risks posed by ultra-small particles.