Participation in voluntary groups is potentially an important way to create health promoting social capital. This paper investigates women's participation in voluntary groups, utilising data from a postal survey of 968 female respondents and in-depth interviews with 30 women. Logistic regression was conducted to examine factors associated with frequency of women's group involvement. Not working full-time, living in a married relationship, and having a university education were all significantly associated with regular involvement. The qualitative data further illustrated some of the ways in which these three factors were linked with women's involvement in groups. We conclude that women who were able to regularly participate were those who already enjoyed levels of social and economic privilege. Policies to promote social capital via participation might focus on identifying what types of group involvement benefit women's health, and increasing the accessibility of such groups to include diverse groups of women