In it first article, the Civil Code establishes that the sources of Spanish law are law, custom, and the general principles of law as well as the circumstances in which each one of them is applied. The Spanish Constitution (SC) is the Law of Laws. It gathers the fundamental rights of the person who should respect the guidelines of the lower ranking. The Law is the guideline having the maximum category below the SC, its elaboration corresponds to the General Courts although the executive power may legislate in certain circumstances (by delegation of the legislative power or by emergency). Executive power elaborates Regulations that are technical developments of the laws. The regulations of the Regional Communities have the rank of law in their geographic setting and for the material in which it has competence. The validly agreed upon international treaties form a part of the Spanish set of rules after being published in the Official State Bulletin. The Spanish legal system is hierarchical, the rules coming from community law are within the peak of the pyramidal structure, with preference on the constitution, followed by laws and rules.