In recent years, hedge fund activists have played a transformative role in the corporate governance of European listed firms by launching campaigns and demanding operational, strategic and governance changes. Originally an American phenomenon, hedge fund activism has been comparatively under-researched from the perspective of European law and the goal of this doctoral project is to fill this gap in European scholarship by analyzing how hedge fund activism plays out in the European shareholder-centric system of corporate governance (in comparison with the U.S. board-centric corporate governance system). It makes four important contributions. First, it shows how EU insider trading rules can affect pre-disclosure investor communications and hedge funds’ wolf-pack formation. Second, it elaborates on the restrictive effect of British, German and Italian takeover laws on the collective submission of shareholder-sponsored director slates. Third, it provides empirical evidence of recent settlements reached between activist hedge funds and European public firms, and fourth, it analyses the discharge of activist directors’ fiduciary duties when serving on British, German, French and Dutch corporate boards.