In this paper I discuss how participation in IT design depends on how actors and IT design is defined. The argument is that participation is intertwined with gender, power and knowledge. The empirical basis for the paper is an ethnographic study of a business process analysis in an IT design project in a Swedish government agency. The frame of reference is constituted by ideas from PD and theories from feminist technoscience, and a central concept is sociomaterial practices. The empirical material is analysed with the help of agential realism. Based on the analysis I discuss how participation in IT design in various ways is intertwined with gender, power and knowledge. One major conclusion is that the women who were the central knowers in the business process analysis became visible as participants. This is related to the debate about women's participation in IT design.