Why are only 6 per cent of US physicists female? And why is women's progress into the upper echelons of the hard sciences so painfully slow? A survey due to be presented this week at the American Physical Society's annual meeting reveals that being part of a dual-career couple can form a critical barrier to the progression of the small number of women working in physics (see page 273).

Many more women physicists than men are married to other physicists, so are in the complicated position of having to search for a job with a physicist spouse. Worryingly, the survey finds that dual-career couples working in science are put in a worse situation by what is described as “institutional ignorance”, “bureaucratic inertia” and what can be summed up as plainly sexist ideas about the role of women in dual-career couples. We should not be overly surprised at this — witness, for example, a recent report from the Massachusetts Institute of Technology that women faculty are systematically rewarded less for professional accomplishments than their male colleagues.

The problems faced by dual-career couples — in any profession — pose a challenge for institutions. If the small numbers of female physicists are to be retained, their employers need to stop ignoring the issue or even making things worse. Most institutions have been slow to identify and deal with the obstacles to employing dual-career couples, yet there are a number of tried and tested ways they could adopt — for example, offering shared or split positions, or running spousal hiring programmes. As the survey shows, these ideas have already been successfully put into practice at a few US higher-education institutions.

With increasing numbers of women taking up scientific careers, the number of dual-career couples in science is likely to continue to grow. Institutions have no option but to face that phenomenon and adapt.