In 1996, after about 10 years of postdoctoral work on both sides of the Atlantic, I took a deep breath and went independent as a freelance bioinformatics consultant and science writer.
I had always been too inquisitive to be a first-class postdoc. I was one of those for whom the research going on in the next-door lab was usually more interesting than their own. If anyone had asked me what aspects of postdoctoral work I found most rewarding, I would have given two answers: talking and writing about science, and helping people solve their problems. I now spend most of my time doing these things.
Bioinformatics, as a discipline, did not exist when I was a postgraduate student in the mid-1980s. Like many bioinformaticians in their 30s and older, I moved into bioscience from a physical science background. I studied for both my first degree and my Ph.D. in the physics department at Bristol University. In my Ph.D. research with Edward Atkins, I studied the structure and function of regular helical biopolymers. After a few months as a programmer, during which I gained valuable experience in the way small businesses work, I obtained my first postdoctoral position in pharmaceutical sciences at Aston University. There, I was a member of a team developing drugs against cancer and infectious diseases.
This was followed by a year at the National Cancer Institute in Frederick, Maryland, working with Alex Wlodawer on the structure and mechanism of HIV protease inhibitors, and by four years at the University of Leeds. During those years, I gained confidence, learned bioinformatics, and picked up a large number of valuable contacts, but I was becoming increasingly frustrated.
My scientific interests were broader but shallower than those of most of my colleagues in a top-rated basic biochemistry department. This way of working did have a few advantages for fundamental research. Looking back, I can see a pattern in those times when I made a substantial contribution to a piece of research: That contribution was often just a suggestion that X's technique might be usefully applied to Y's problem. However, even that did not stop me from thinking of myself as a Jack of all Trades ... with the obvious corollary.
To make things worse, I was one of the few researchers who thoroughly enjoyed lecturing. Paradoxically, in the age of research assessment exercises, I found this to be a handicap to my obtaining a position as a lecturer. I began to think that following my rather vague ambition to try working for myself would be more rewarding than staying in academia. I started work on my first few consultancy contracts before I had even made the final decision to leave Leeds.
I had always enjoyed writing--even writing papers--and from the beginning, I hoped that that might become an important part of my "portfolio career." It was a chance encounter, however, that gave me my first step on the ladder of professional journalism.
In 1995, I was invited to give a talk at the British Association science festival in Newcastle. While there, I met Frank Burnet, editor of the Biochemical Society's magazine, The Biochemist . He had been looking for a bioinformatician--a "computer wonk"--who could explain the more mathematical aspects of biochemistry in a way that would interest those at the bench. One commissioned article led to the birth of the regular "Cyberbiochemist"  feature in that magazine, which I have edited for 4 1/2 years. That one regular column was enough for editors to start taking me seriously as a writer.
Many of my collaborators and former colleagues have been invaluable in supporting my career transition. Two of those I owe most to are David Moss, of Birkbeck College , London, and Mariusz Jaskolski of the A. Mickiewicz University  Poznan, Poland.
I first met Mariusz as a fellow visiting scientist in Frederick, Maryland, in 1991. At that time, just after the fall of the Wall, there was immense excitement and optimism throughout the expatriate eastern European community. I shared Mariusz's hope that he would, shortly, be able to set up the first protein crystallography lab in his home country. One of my first consultancy contracts was to run a training course in computer techniques for postgraduate students in this new lab. David Moss, as coordinator of teaching at the School of Crystallography, Birkbeck College, had set up the first UK-based university course in a biological subject to be taught entirely using the Internet: "Principles of Protein Structure." 
I started working for the School of Crystallography in September 1996. My work there was initially funded by a grant from the Open Society Institute. This also allowed us to extend this form of education to students in eastern Europe who otherwise would be unable to afford Birkbeck's modest fees. Two of Mariusz's Ph.D. students will shortly be among the first cohort to be awarded Birkbeck's new M.Sc. in structural biology using the Internet.
I have now developed a varied career with three basic strands: the technology of teaching in the biosciences, bioinformatics consultancy and research support, and science writing. The first includes, besides my work at Birkbeck, work as an associate lecturer on the Open University's (OU's) M.Sc. in science  program. It has been interesting to compare the technology used by the OU--a combination of computer conferencing with more traditional distance learning techniques--with Birkbeck's Internet-only courses. Although work for the OU is not very profitable, at least by consultancy standards, it is extremely rewarding. There are few e-mails that I am more pleased to receive than those from students thanking the OU for helping them obtain promotions or new jobs.
University and government departments, and small biotech companies, employ me to advise them on bioinformatics and structural biology research. Some companies also employ me as a writer, to prepare public relations materials and industry "white papers." I am involved in bioinformatics training courses for the Human Genome Mapping Project resource centre  and elsewhere, most recently in Italy and Portugal.
As a journalist , my clients include the Elsevier Trends and Lancet journals, Scrip magazine, and the Times Higher Education Supplement. I continue to be involved with research at a high level, and have so far managed to fulfil my ambition of coauthoring one peer-reviewed paper a year.
Two years ago, Birkbeck took me on the payroll as a part-timer. Part-time employment has obvious advantages for a freelancer, providing a necessary financial "cushion" for those (fortunately rare) occasions when all my clients forget to pay me at once. However, I am extremely fortunate in that my senior colleagues, particularly David Moss, understand that I am equally committed to my freelance career. My working life is varied and unpredictable, and I need to be able to adapt my commitments at Birkbeck to fit in with the rest of an extremely busy schedule.
Working as an independent expert is excellent as a second career, but I would not recommend that anyone embark on it without substantial previous experience working for an employer. You need a network of contacts and at least a few promised commissions before starting out. You also need highly developed organizational and communication skills, the confidence to go out of your way to seek work--and a good accountant. My first year was quite difficult financially and would have been much harder without backing from my parents.
I value many things about my work: the variety, the chance to travel, and interactingwith people at high levels in many bioscience-related professions. I learn something new almost every day, and no two weeks in my working life are the same. It would take an extremely good offer indeed to tempt me back into a more conventional job.