Competition law is a recent development in Saudi Arabia, with the first law issued in 2004. Initial enforcement was ineffective due to legislative and institutional shortcomings. Significant reforms established an independent competition authority and updated legislation. Combined with nearly two decades of enforcement experience, these developments make it timely to examine how public enforcement of competition law can be optimised in Saudi Arabia. The research employs legal-doctrinal and comparative methodologies, focusing on Egypt and the European Union as key benchmarks. A socio-legal approach, including institutional analysis and elite interviews, complements the study due to the scarcity of published decisions and academic literature on Saudi competition law. The thesis examines four central aspects of public enforcement: the objectives of competition law, the enforcement toolkit, institutional design and judicial review. The analysis begins with the Saudi legal system's foundational influence on competition enforcement. The Competition Law identifies multiple broad objectives. Yet, these broadly defined goals lack hierarchical order or substantive interpretation by agencies or courts, creating uncertainty in enforcement priorities. The law provides various enforcement tools, including fines, leniency programmes, settlements and compliance mechanisms. Fining policies have evolved from fixed amounts to turnover-based calculations, though fixed fines remain prevalent in practice. Leniency and settlements represent positive steps, but their conflation within a single legal provision has led to operational ambiguity. Compliance programmes are promoted but lack financial incentives such as fine reductions, potentially limiting their uptake. Institutional independence has improved with the establishment of the GAC. However, ministerial representation on its board undermines autonomy. A shortage of academic expertise in competition law and economics further constrains capacity. While the GAC holds exclusive enforcement authority, ineffective cooperation with sectoral regulators risks undermining its efficacy. International engagement remains limited, with only one cooperation agreement signed with Egypt. Judicial review by administrative courts is crucial for ensuring enforcement legitimacy, but the absence of published case law hinders analysis. Specialised training for judges along with specialised court divisions, could significantly improve judicial outcomes. This thesis concludes that, despite progress, strategic refinements in enforcement practice, institutional autonomy and judicial expertise are essential for a robust competition regime in Saudi Arabia.