While the various initiatives in several jurisdictions to impose ex ante regulation on “digital gatekeepers” – i.e., large online platforms that are necessary intermediaries between business users and their customers, and which are typically protected by high barriers to entry – have attracted considerable attention, the purpose of the present paper is to contribute to the policy debate on the equally important need to strengthen effective antitrust enforcement in digital markets. The focus of the paper is on possible adjustments to the current competition law framework or its enforcement with respect to unilateral (single-firm) conduct. Specifically, it examines four proposals to improve the effectiveness of antitrust enforcement in digital markets. First, it argues in favor of revisiting the error-cost framework and considering the introduction of presumptions of anti-competitiveness in limited circumstances. Second, it makes the case that competition authorities should make greater use of restorative remedies with a view to re-injecting lost competition in the market. Third, it discusses the need for greater focus on harms to quality and innovation. Fourth, it is argued that in circumstances where competition has been irreparably harmed and cannot be restored, competition authorities in the EU should consider pursuing exploitative cases.