This study discusses in its first part the concept of archive as it was described in the Romanian and Hungarian secondary literature and debates the role of the archive, detailing its area of competence throughout time and its double goal, the safe preservation and the insurance of accessibility of documents. Nowadays, the archive fulfills three main functions, namely, scientific, cultural, and administrative. The history of the main tasks assigned to archives, such as the organization and the methods of preservation of documents, emphasizes the importance of the 1764 regulation decreed by the Viennese authorities, entitled Nova Manipulatio, which stipulated the mandatory character of both, the recording of documents and the creation of search indexes. In the eighteenth century, following the Austrian pattern, the archives of government offices and juridical authorities were established. The work of the juror archivists was outlined and regulated by governmental norms and inner administrative orders. The article analyzes primarily the functioning of the Roman-Catholic archives in Transylvania (The archive of the bishopric and of the chapter of Alba Iulia) and their norms and regulations. The activity of the Roman-Catholic archives was regulated through inner norms (instructions of the church) and external (lay). These were discussed based on the sparse secondary literature and on the archival primary sources preserved in the Archive of the Roman-Catholic Archbishopric in Alba Iulia. The most effective regulation governing the establishment, preservation, and state of the ecclesiastical Roman-Catholic archives, before the coming into force of the Codex Juris Canonici,was the constitution entitled Maxima vigilantia of Pope Benedict XIII. After the survey of the ecclesiastical and lay regulations concerning the archives of the Catholic Church, follows the presentation of the decrees issued by the Roman Catholic diocese of Transylvania, and, finally, some examples of the scientific and practical employment of the archive of Alba Iulia are given. The profile of the archivist was described starting from the norms and instructions for the functioning of ecclesiastical archives. In the eighteenth and nineteenth centuries, the ordering and administration of the archives of ecclesiastical institutions was carried out by notaries, secretaries, scribes, and in the case of the archives of the authentication places (loca credibilia), by requisitors and clerics. For lay institutions, the office of archivist was established in mid-eighteenth century. In the Roman-Catholic church,the ordering and administration of documents was performed by clerics, while in the Protestant churches, notaries carried out this activity. From the archival material and normative documents one can extract information concerning the training of the archivists and the requirements of their office. First of all, they were required to possess excellent Latin paleographical skills and knowledge of the Hungarian language, juridical instruction, loyalty, and discretion as regards keeping the secrets, as well as the ability of calligraphic writing. As regards the content of documents, the archivists were obligated, under oath, to preserve the secret.