The Declaration of Heirs has been treated by different authors from a doctrinal point of view focused on basic models of research, but not from the one that experience and jurisprudence provides, however, in its result has been general criterion that the lack of will of testamentifaction leads to the rules of succession mortis causa is regulated by the criteria of the Civil Code and Civil Procedure. In the present work the reader has in his hands a useful tool that will serve for those legal professionals or those who are already immersed in the title of "lawyers" and carry their first cases of Declaration of Heirs where the content of what our substantive norm says regarding the intestate succession and the need to materialize it and merge it with the adjective or procedural norm in order to achieve an adequate result for our clients, focused from a jurisprudential and practical perspective so that the reader has a clear vision of how to practice this matter treated.