This book seeks to deepen the principle of legal equality, its scope and content in front of certain population. In the same way as its extension to other subjects, under the methodology of legal dogmatics, it seeks a bibliographic and jurisprudential review within the project “The challenges of contemporary private law in the context of the constitutional debate and new developments in the economy”, of the Group Study in Private Law and Intellectual Property in the line of research Private Law. The foregoing within the framework of the constitutionalization of national private law, and comparative private law studies at the Catholic University of Colombia. The purpose of this book is to offer to the academic community states of the art that facilitate the subsequent formulation of research projects to allow the study, understanding and dimension of the subject of rights as a category that transcends the traditional concept of person in their search for legal equality in situations related to age, sex, gender, disability, economic conditions, and others. All within the era of the constitutionalization of private law.