This chapter provides a detailed examination of Friedrich A. von Hayek’s theoretical approach to law, presenting it from an evolutionary perspective informed by the Scottish Enlightenment tradition. Hayek proposes a ‘fourth position’ on law that is distinct from the views of legal positivists, iusnaturalists and legal realists. He specifically challenges constructivist interpretations that view social orders as arbitrary creations. According to Hayek, law is a spontaneous order that emerges from the interactions of individuals without any deliberate design or specific purpose. It is a combination of spontaneous rules from cosmos order and consciously created rules from taxis order. The chapter argues that law is older than legislation and comprises heterogeneous elements, including abstract principles, values, habits and both deliberate and unintentional rules that evolve together and interdefine each other. Understanding this complex system requires recognising the underlying values that guide individual action, which cannot be reduced to mere empirical observation. Finally, the chapter highlights the particular role of judges in resolving disputes by identifying and articulating unarticulated principles and expectations, thereby maintaining and improving the existing legal order.