The collection has grown over time through the efforts of faculty members, especially those in history, literature, and Balto-Slavic linguistics. Russian language materials predominate, followed by Lithuanian, Polish, and Ukrainian. The Library also has more than 1500 volumes in Armenian, primarily in history and literature, and small clusters of books in each of a dozen other East European and Caucasian languages. The Lithuanian component of the collection is strong. In 1952 the Library acquired the library of Dr. Jurgis Saulys, and this collection, steadily enlarged up to the present time, makes Penn one of the best places in the country for the study of Lithuania.
The Library currently subscribes to over 150 serial publications in all languages in the Russian and East European field; these include current newspapers, basic journals, and monographic series and the major Slavic studies series produced by U.S. and European Slavic studies centers. Some older materials have been acquired on microfilm. Recent efforts include strengthening holdings of material on the history of Russian and Eastern European art and of Russian scholarship on Central Eurasia.