the Head of the Longitudinal Study Development Team. Recent publications include

We focus here on the issue of the retention of highly qualified women scientists in science-based employment in England and Wales. Using linked census records from the Longitudinal Study 1971-1991, we show that women's education and employment rates in science, engineering and technology increased somewhat, although some fields show persistently low representation. We then compare the retention in employment of women with health-related degrees with that of women with degrees in science, engineering and technology, showing that the latter group has markedly lower retention rates. Those who stay on in science-based employment have children later than other types of graduate and their rates of non-motherhood are higher. Four-fifths of women in health-related occupations were mothers, compared to only two-fifths in science, engineering and technology. Our findings have implications for policy-makers who wish to make best use of the knowledge base: attention should be paid to retention, as well as the more usual focus on qualifications and recruitment. The findings also suggest the potential for institutionally-base