Some works of investigation have introduction, which is very important in the same, therefore, the present tendr this part, the one that serve to have a global approach on the investigated subject, in such sense in the referred one hopes to offer to a global approach of the subject matter of study and this form to have previous knowledge of the subject study matter, consequently we hoped to know better east subject, which properly is a jurdica discipline, which is little well-known on the part of the treaty writers mainly in the Peruvian right. The compared right must be studied by the jurists and right students, thus in the present we will study the same, to be around the ltimos advances of the world-wide right, putting record that the same must be studied in the Peruvian right, nevertheless, have dedicated few studies to him, thus we hoped that in the future currculas of right study is added to all the, not slo in post degree, but tambin of pre degree, consequently will be kind to the advances of the foreign right that they can be received or be transplanted, and also by all means to take into account the prevailing criterion in the compared right. That is to say, this jurdica discipline is very important in the right, and must be studied by far taken care of not to induce to error to the readers and investigators who by the way can be jurists and students of right, in such sense for some referred slo podra to exist between rights of different states, for example between the Peruvian civil right and the mercantile right francs or between the Spanish aeronutico right with the American csmico right, among others assumptions, thus podra not to exist between two branches of the right of a same state, nevertheless, this is mistaken, because east type can become of comparisons, for example of the South American right in two centuries different or from straight world-wide slo in the referred thing to sources of the right in two centuries different, but slo within the mercantile right, or of the Spanish right within two centuries different, among others supposed..