The Library holds an extensive collection in the field of international relations and political science. It was historically built up by the library of the Graduate Institute of International Studies (created in 1927) and the library of the Graduate Institute of Development Studies (created in 1961).
It has received many donations over the years, including documents dating back to the beginning of the 20th century. The Library holds a large collection of diplomatic documents of the major great powers.
The former Graduate Institute of International Studies library had also built up an extensive collection of books dealing with socialist ideologies and movements, the Soviet Union, and other socialist countries.