This report makes the case for mandatory corporate gender quotas in Ireland. It underlines the efficacy of gender quotas to deliver significant increases in gender balance on corporate boards, and includes a review of the proposed EU Directive on Gender Balance on Boards. The report explains what legislative corporate quotas are, and the difference between them and voluntary targets. Drawing on international evidence, it details the limits of voluntary quotas and targets. Acknowledging where some progress has been achieved in Ireland, it illustrates how such progress has now stalled and why Ireland would benefit from a system of mandatory quotas. Through a series of international case studies, the authors of the report detail what is distinctive about a legislative approach to gender quotas, where they have worked well and under what conditions. The report also provides evidence of the limits of voluntary and soft targets to realize significant and durable progress in achieving gender balanced boards.