Since its creation and during these fifty years of activity, the Institute has welcomed 166 members.

In order to be admitted, the candidate has to follow a procedural requirement and have attended at least two Conferences. Furthermore, the candidate must submit communications in the mentioned International Conferences (Asamblea General, 22/09/2005).

The applicant must submit a written request for application and send it to the Secretariat of the Institute. The application has to be submitted to the permanent headquarters in Argentina or to anyone of the secretaries attending the Conference. In addition to the two communications published, the submitted documents must prove that the candidate has developed or develops research directly related to History of Indiano Law. These research papers must have been published in books and/or scientific journals in order to evaluate that the candidate is committed to Indiano legal history.

The application must also be supported by at least four members of the Institute, none of them being members of the Executive Committee. (Asamblea General, 22/09/2005).

The request for application shall also include the candidate's curriculum vitae. Both curriculum and application will be written in Spanish and submitted with copy. (Asamblea General, 22/09/2005).

Applications will be forwarded by the Secretaries of the Institute to the Executive Committee held during the Conference. The committee shall evaluate them and make the proposal to the General Assembly. (Estatutos, II.4, c).

Finally, the General Assembly shall make an analysis of the applications based on the proposals of the Executive Committee and proclaim, if any, the new members of the Institute (Estatutos, II.6, b)