This work, which is part of a larger project, divided into a first part referring to the regulation of the constituent process in Chile and another referring to its operation – will try to describe the constitutional and legal regulation of the constituent process in Chile from 2019 to 2022, from its material origins found in the Social Outbreak, such as in the Agreement for Social Peace and the New Constitution of 2019, and then review its formal sources, mainly, the constitutional reform law No. 21,200 and the subsequent constitutional reforms that modified its original regulation.