The Archives of the Republic of Slovenia (ARS) maintains a register of Slovene archives kept in Austria, Italy and Hungary, countries which once controlled Slovene national territory. Some other international record groups are kept in Slovenia, for example the archives kept at the Historical Archives of Ptuj related to the Scottish Leslie family, lords of Ptuj castle in the middle of the 17th century. The Leslies were originally a Hungarian family (Bartolomej Leslie) that moved to Scotland in the 11th century and earned their wealth there. Most significant for Slovenia and Ptuj was Walter Leslie, who served Austrian king Ferdinand II in the 17th century. Slovenia is also connected with the Leslie family through Wilhelm Graf von Leslie, who was Bishop of the Ljubljana Diocese from 1718 until his death in 1727. Bishop Leslie studied in Graz and Vienna, served in Rome and later worked as a university professor in Padova (Dolinar, 2001). Some archives relating to him are kept in the Archiepiscopal Archives of Ljubljana, mostly found in the record group the Diocesan Archives, Ljubljana.

Without registering the archives kept in the central archives in Vienna it would be almost impossible to study Slovene history, since during Habsburg times the archives of central Austrian institutions were kept in Vienna, while the archives of provincial institutions were kept in the provinces themselves, eg Carniola. . The archives in Maribor, Ptuj and Celje are responsible for Austrian Styria, while the archives in Koper and Nova Gorica are responsible for the Italian archives in Venice and Rome. So far the ARS has published guides to the Central State Archives in Rome, to district, regional and trade archives in the Czech Republic, and to the Central State Archives of the Czech Republic in Prague. It is currently working on projects in Germany, Austria, Russia, Italy, the Vatican, Hungary, France, England, Croatia, Canada, the USA, the Czech Republic, Malta, Yugoslavia and Spain. The Slovene Film Archives is also working on the registration of films in the Imperial War Museum in London, the Croatian Cinematheque in Zagreb, the Yugoslavian Cinematheque in Belgrade, the Austrian Film Archives in Vienna, the German Film Archives in Berlin, the Luce Institute in Rome and the French Film Archives in Bois d'Arcy.

International agreements in the field of culture include the exchange of technical literature and seek to ensure the financial means for their realisation. The ARS has such agreements with archival institutions in Austria, Poland, the Czech Republic, Croatia, Macedonia, Russia, Montenegro, Bosnia-Herzegovina and Serbia.

Since 1992 the ARS has been a category A member (national archives) of the International Council on Archives (ICA). The Archival Association of Slovenia (AAS) is a category B member (national archival associations) of ICA, and the Historical Archives Ljubljana and the International Institute for Archival Science (IIAS) are category C members (other archival organisations). Since 2001 both the ARS and the AAS have been members of International Council on Archives (ICA), European Regional Branch (EURBICA). Since 2000 the ARS has also been incorporated into the European Board of National Archivists (EBNA, comprising directors of national archives of EU countries), which assembles twice each year and is chaired by the director of the central archival institution of the presiding EU member. Since 2006 the ARS has also been involved in the EU work of the European Archives Group (EAG) in Brussels. The Slovene Film Archives is a member of the International Federation of Film Archives (FIAF) and the Association Cinematique European (ACE); and the Sound Archives of the Institute of Musicology, ZRC SAZU is a member of the International Association of Sound and Audiovisual Archives (IASA), the Audio Engineering Society (AES), the International Council for Traditional Music (ICTM), the Komission für Volksdichtung (KfV) and the Societe International de Ethnologie et Folklore (SIEF).

The ARS took part in MOSAIC within the Partnership for Peace programme, and in 2000 organised a seminar on archive information technology for archivists of new states of the former Yugoslavia, partly funded by the Council of Europe. The ARS is also engaged in the international project 'Historical Documents of the Napoleon Period on the Territories of Austria, Italy, Slovenia, Croatia and Montenegro' with participating countries and France. The guidebook to record groups and collections for that period in all mentioned countries was published in 2005. The project was also partly funded by the Council of Europe, the National Archives of France and the national archives of participating countries.

In the fields of restoration and conservation, it is worth mentioning a successful co-operation between the ARS and Professor Christopher Clarkson from Oxford University, who held a series of five two-week staff training workshops on book conservation from 1997 to 2002, in co-operation with the National and University Library (NUK) of Slovenia and the Conservation Society of Slovenia. In honour of the 40th anniversary of the first Paper Restoration Workshop in 1996, the ARS organised an international symposium with the title 'Writing and Image', accompanied by a collection of scientific papers and an exhibition catalogue in English. The ARS, the National and University Library (NUK) and the National Gallery of Slovenia organised the international symposium 'Exhibiting Archival and Library Material and Works of Art on Paper: Standards in Preservation' on 5-6 June 2003, also in association with the Committee on Preservation of Archives in Temperate Climates (ICA/CPTE). The Slovene Film Archives and the Slovenian Cinematheque organised the 61st international congress of the International Federation of Film Archives (FIAF) in Ljubljana (June 5-16, 2005) in honour of the 100th anniversary of Slovene film. The congress theme was ethnological film - see the FIAF Congress Ljubljana 2005 website.

The Historical Archives Ljubljana has members in the European Association for the History of Medicine and Health (EAHMH). Since 2000, the Historical Archives Ljubljana has taken part in a joint project of the archives of all EU capitals, entitled DACE (Model for Description System of the Historical Archives). This institution has also worked with the Town and Provincial Archives Vienna on the exhibition 'Slovenia and Vienna', which was presented in three Slovene towns and at Vienna's Austrian Science Academy in 1995. The Regional Archives of Maribor has on several occasions organised an International Archival Research Camp in the border region between Slovenia and Hungary, together with an exhibition of collected archival material staged on both sides of the border. The Sound Archives of the Institute of Musicology, ZRC SAZU, and the Phonogrammarchiv Vienna have set up an international project of preservation and reorganisation of audio material. The Institute is also making arrangements with other important institutions for joint research projects in ethnomusicological heritage, including the Golda Meir Library of the University of Wisconsin, Milwaukee USA; MTA Zenetudomány Intézet, Budapest, Hungary; Institut ruskoy literaturi, Puškinski dom, St Petersburg, Russia; and Volksliedarchiv, Vienna). The Slovene Film Archives also co-operates with the British Film Institute in London in the field of maintenance and cataloguing of film archival material.

A few international exchange and co-operation agreements have afforded Slovene archivists the opportunity of obtaining further education at specialist institutions such as Archivschule Marburg in Germany, Stage technique international d'archives (STIA) in Paris, the Central European University Budapest and the Amsterdam-Maastricht Summer University (McLuhan Institute) in the Netherlands.

A Visiting Arts research report from 2003 entitled 'Mapping the Infrastructure of the Museums, Archives and Libraries Sector of Slovenia' was carried out on behalf of the Museums, Libraries and Archives Council of the UK (then called Re:Source) with the assistance of the Museums, Libraries and Archives Council and other Slovene experts. The research dealt with current issues in the Slovene archives sector, including professional standards of practice, building management, collections management, user staffing, research and scholarship, building management, archival holdings, use and accessibility of archival holdings, archive holding management and professional standards of practice, information technology and digitisation of archival holdings, digital archive projects, education and outreach, cultural diversity and international collaboration and exchange. According to the research, the key developmental needs in the Slovene archives sector are: international exchange and co-operation in the field of information technology in the archival sector, especially digitisation; lectures and seminars by visiting professors providing further professional education of archival staff, particularly covering subjects such as records management, electronic record keeping, preservation (chemists, restorers, or bookbinders), presentation and promotion of archival activity in society; international assistance in the registering projects; co-operation in the publishing of guidebooks (especially bilingual ones) on registered materials; assistance with the co-ordination of terminology; compilation of a terminological dictionary and translation of foreign archival literature into Slovene (eg standards, recommendations, technical reference books, textbooks); work placements in or exchanges with specialised departments of various institutions; and exchanges of staff and publications with special archival institutions such as music archives and the archives of universities, medical institutes, theatres and emigration departments.