In the same year he joined the staff of the Hermitage Museum in Leningrad (now Saint Petersburg).

Later on, he teamed up with the linguist Sergei Starostin to produce authoritative studies of the Caucasian, Afroasiatic, and Hurro-Urartian languages.

Diakonoff was honored in 2003 with a festschrift volume published in his memory, edited by Lionel Bender, Gábor Takács, and David Appleyard.

In addition to articles on Afro-Asiatic languages, it contains a five-page list of his publications compiled by Takács.

Igor's first wife Nina Dyakonova (1915–2013) was a historian and critic of English literature, with a special interest in English Romantic poetry of the early 19th century (Keats, Byron, Shelley) and its reception in European and Russian literature.