The judicial protection of fundamental rights of Article 20 of the 1980 Chilean Constitution has expanded steadily. This has happened over the past four decades in terms substantive and procedural. This article distinguishes three phases in the procedural dimension of this expansion-an administrative contentious procedure, a limit of self-protection among individuals and a universal jurisdiction-, disaggregating the five main challenges that all these periods represent to the judicial system. The paper proposes to interpret this expansive phenomenon of this precautionary measure of urgency in exploratory terms, that is, as a way to identify the aspects in which the judicial system of Chile is deficient, either because it needs a definition (or a redefinition) in procedural terms and/or in organic terms. Along with it, the paper identifies the academic solutions that have been proposed to alleviate this type of challenges.