The number of careers in science is expanding, which means the call for talented minds is at a peak

It was in the era of Prime Minister Margaret Thatcher - herself a qualified research chemist - that the fear of a scientific "brain drain" became headline news. As thousands of newly qualified physicists, chemists and biologists opted for cushier, better-paid jobs overseas, the science establishment warned that Britain was being denuded of some of its brightest scientific talent.

Thirteen years since Premier Thatcher was deposed, the demand for science graduates has exploded beyond all expectations, says The Royal Society, as new industries have grown up to reflect new scientific discoveries. Be they roles in developing cloning or genetic modification, the work of contemporary scientists appears to be more mainstream than ever before.

In the view of Sir Alistair MacFarlane, chairman of the Royal Society's education committee, the number of potential career paths for today's young science graduate - and that's outside the traditional field of teaching - is enormous. "In the old days," he says, "you did physics, chemistry or biology at university and then specialised in those areas at work. Today, there is a huge range of inter-disciplinary technologies in biotechnology, computer science and nanotechnology to consider."

If traditional science industries have expanded out of all recognition, then so too have the roles within them. "It is no longer simply a case of shaking test tubes in a lab," says Sir Alistair. "For those with scientific qualifications there is now a choice between working in a scientific capacity and actually managing the people in those labs; some of whom will be difficult prima donnas."

Sir Alistair adds: "The rise in managerial positions for scientists has been enormous as the old stereotype of a lonely figure in a white coat has given way to team-working and vital people management skills. In short, today's scientist has to be able to work with others."

Perhaps more intriguing is the growth in opportunities for what may be termed "spin-off" industries and professions as developments in science continue to impact on society. From pressure groups such as Friends of the Earth to civil service posts in the Department of the Environment, Food and Rural Affairs, there is an enormous need for trained scientists to fulfil jobs that are far removed from the traditional science lab.

For example, 30-year-old Elizabeth King has a BSc double honours in chemistry and biochemistry from the University of Southampton, as well as a PhD in bio-organic chemistry. She now works as a European patent attorney. Her role involves advising clients in sectors such as pharmaceuticals or food on how to apply for and protect patents.

More traditional is the career path of Jack Williams, 26, a BSc in chemical and pharmaceutical science from the University of Sunderland and now an associate scientist and analytical chemist with a major pharmaceutical company, where he is involved in drug development and safety.

While salaries for many scientists are still far higher overseas - some 25 per cent of scientists choose to work abroad according to a Royal Society survey of three years ago - the announcement by Chancellor Gordon Brown in 2000 of a £1bn investment programme for scientific research may have gone some way towards reassuring the scientific community that the UK is keen to improve salaries, resources and conditions for its "boffins".

Although Britain has historically had a reputation for being rather anti-science - a current case in point being the negative attitudes towards genetically-modified foods - there is a clear determination to invest in home-grown research into genetics, pollution management or fibre optics.

According to Dr John Johnston, manager of education communications at the Royal Society of Chemistry, the supply of and demand for qualified chemists is, at present, notably well-balanced. "In 2002, around 3,200 chemists graduated in the UK, only 300 fewer than the total number a decade before," he says.

"Anecdotally at least, the chemicals industry and the pharmaceuticals side of the sector appear to have just about the right number of graduates to go around and there is little talk of shortages at present." In terms of gender diversity, the news here is good too. With male and female graduate chemists coming out of universities and colleges at about the same rate, Dr Johnston believes that there is now a "good female cohort" within the profession.

Less well represented among women are jobs in physics. Perhaps the least glamorous of the three traditional sciences, physicists are much misunderstood. This view is shared by Peter Main, director of education at the Institute of Physics. "Our graduate cohort, at 2,500 per year, is unchanged from 20 years ago, but only around 20 per cent are women. We are doing a lot of work to make physics as a discipline more attractive and less dry to undergraduates as a whole and to women in particular, but most studies of scientists suggest that chemistry or biology are more attractive to women than physics."

Dr Sarah Dunkin is one of the Royal Society's "Dorothy Hodgkin fellows", a scheme that provides funding for scientists in the early stages of their postdoctoral careers - a time when many researchers, particularly women, tend to leave science altogether. Her current research involves understanding more about the moon. She is closely involved with SMART-1, Europe's first moon mission, and has helped develop a technique to provide detailed information about the composition of the moon's surface and to help answer questions about its origin and evolution.

Dr Dunkin's future projects will include the planned trip to Mercury in 2011, again under a European flag.

Back on Earth, physicists tend to be strong at problem-solving and at maths and, says Main, an increasing number of them are finding lucrative jobs in the bio sciences and even in the City. "It used to be said that physics was the science of the 20th century and biology is the science of the 21st century, but physicists are teaming up with biologists to discover more about DNA - which was actually discovered by a physicist - and the latest developments in, say, single molecular manipulation.

"Although careers advisers can be negative about career opportunities for physicists, today's physics graduate can find him or herself working in anything from pharmaceuticals to the very heart of the Stock Exchange, working on financial modelling."

If the pharmaceutical industry is in a strong position in terms of graduate supply, then the situation for scientists in general is more complex, says Sir Alistair, who believes that there is a shortage of first degree scientists.

"I would say that in terms of career scientists and research workers such as MSc and PhD students, we probably have enough. But given the enormous growth in scientific industries, what we are really short of are the Bachelors of Science who, having gained a basic grounding in scientific thought, go on to take up a role in industry, rather than continuing to devote their talents to more academic research."

The Royal Society notes too the lack of scientific entrepreneurs in Britain. Despite being a nation famed for its innovative streak, it remains the case that British scientists are often unable to turn their brilliant inventions into hard cash.

Sir Alistair says: "Aside from inventors, we need to nurture the really top-flight scientists, the potential Nobel prizewinners who are head and shoulders above their contemporaries. Retaining top talent is an important issue for all British scientists."