In this paper we address the regulation of public aid, its characteristics and advantages for economic recovery based on a necessary conceptual delimitation, its economic foundation and its different regulatory areas, focusing on its importance in the current context of crisis created by the pandemic of Covid-19.With this objective in mind, we will successively expose its regulation in three different areas: multilateral, regional and national.In its multilateral dimension, we will focus on the rules contained in the framework of the World Trade Organization (WTO), where we will make a critical review of its current situation and its possible reform, highlighting the unilateral response of the European Union, adopting its own rules to control subsidies from third party countries in the European market.Next, we will analyze the rules on public aid “State aid” contained in the “Treat...