This article systematically reviews 35 empirical articles on the topic of networks and career advancement into academic leadership positions. Our objectives in this systematic review are to clarify: (1) the functions that networks fulfil; (2) the outcomes of these functions in terms of career advancement; and (3) whether networks are likely to result in more or less career advancement for women compared to men. Four databases were searched using the PRISMA (preferred reporting items for systematic reviews and meta-analyses) approach to select eligible studies published between 1990 and 2019. We distinguish three different functions that networks may fulfil: operational, developmental and strategic. Mixed results are found for the operational and developmental network functions, while the results suggest that the strategic function contributes to career advancement, particularly for men. The reason for this can be found in the masculine academic context. Our findings implicate that a solution involving equal network opportunities needs to be taken up by the academic community as a whole. To further develop the research field, we call for: (1) more consistent conceptualisation; (2) more attention to the multiple functions of networks and networking behaviour; and (3) more advanced study designs.