I interviewed women in different fields of biological science and analyzed the interview data by picking out emerging themes. I compared these themes with issues in the feminist literature and with accounts from the social studies of science. Women in biology are far from developing alternative epistemologies, but see themselves as different from their male colleagues in several important respects. They expressed the difficulties in balancing demanding scientific careers with private lives which usually include partners and often included children. At the same time, single women often face problems which married women do not. I conclude that women scientists married to scientists in different specialties may be particularly advantaged. I examined interviewees' attitudes towards collaboration and cooperation both within their laboratories and between interviewees and their scientist peers. I found women biologists frequently describing caring and non-hierarchical relationships within their laboratories. They contrast these with the ambitious and authoritarian attitudes of their male peers. They had a tendency to either work on projects only within their own laboratories. Several described difficulties experienced in collaborating with other investigators. I suggest that there are a number of factors which lead to women scientists publishing less on average than men in science. Among these are numerous competing demands upon women's time, problems with collaboration, and differing personal expectations to those of men. / Ph. D.