The files consist of documents, notes, minutes of meetings, analytical reports, and maps regarding the political situation in Cyprus, that Achilleas Antoniades acquired and used during his diplomatic career. Materials primarily document the period from 1974 to 2009, although some earlier materials from the 1950s and 1960s are also present. While many documents are copies of official records, minutes, and related materials that Antoniades gathered for use in his diplomatic functions, there are also some original documents, as well as Antoniades's notebooks containing his personal record of meetings and other notes. Antoniades's files document several major periods of development in the history of Cyprus in the late 20th century, including the years before and during the Turkish invasion of Cyprus in 1974 and the initial intercommunal talks in the late 1970s; the military coup in Turkey and the unilateral declaration of independence by the Turkish Cypriot community in 1983; the aftermath of the unilateral declaration of independence and the election of President Vassiliou in the late 1980s; the inconclusive intercommunal talks of the 1990s and the application of the Republic of Cyprus for accession into the European Union in 2001; the period of the Annan Plan up to the referendum on reunification in 2004; and the accession of the Republic of Cyprus to the European Union in 2004 and post-accession developments, including documents related to Antoniades's appointments as High Commissioner to Australia from 2004 to 2007 and Ambassador for the Republic of Cyprus to the Czech Republic from 2007 to 2009.

Materials are arranged and described based on a box inventory provided by the donor. They are grouped by chronological time periods of major political developments, with documents filed by the period to which they pertain rather than strictly to the date of their creation. The collection is unprocessed below the box-level.