A factor often brought forward in explanations of interest group success in advocacy is their ability to provide decision-making processes with relevant knowledge and expertise. The European Women’s Lobby (EWL), as the main European level women’s interest group, provides European institutions with “expertise” and “gender expertise”, but what does this mean? The paper opens up the black box of one of interest groups’ proposed key success factors, exploring different meanings and categories of expertise revealed by EWL activities. . Our analysis, based on a systematic and extensive reading and coding of EWL documents, suggests a varied set of expertise categories. Particular attention is given to how the EWL relates to scientific evidence and expertise and to what we refer to as “representative expertise”, the EWL’s proposed expertise in representing European women, and “moral expertise”, the expertise in arguing for EWL interests as a just cause. These findings are discussed in the context of a broader theoretical discussion of the expertise concept, as well as the ongoing debates on the “expertification” of gender equality policy making and feminist civil society and implications for democratic legitimacy.
