The implementation of public policies involves knowing and analyzing the different instruments of public intervention from a transdisciplinary perspective involving legal, economic and political aspects, as this allows to broaden the understanding of the tools available to deal with public issues. In this sense, this paper seeks to present in an integrative and systematic way what have disciplines such as public law, the economy of the public sector and the political sciences, especially public policies, understood for public policy instruments. It takes a particular look at this latter approach and shows why this is the most comprehensive approach. Regarding the methodology, this text is the product of qualitative, theoretical, descriptive and exploratory research of a documentary nature. Among the main findings, intervention instruments were found to guide human behavior towards achieving certain public objectives, constitute the rules of the game and, therefore, serve as institutions that illuminate public action. They are also tools to correct market failures and achieve economic efficiency. Nevertheless, they are not limited to the formal technical and institutional two-dimensional nature of economics and law. Nowadays, the study of intervention instruments must be done in accordance with public policies; it must enable progressing towards context-sensitive governments, the diversity of actors, more active citizenship and the particularities of public affairs.