This series is composed of Hirschman's writings, reviews of his book The Strategy of Economic Development (1958) in various languages (including German, Italian, Portuguese, and English), and a research file of correspondence, memoranda, and reports pertaining to agricultural development efforts in Colombia by the International Bank for Reconstruction and Development (IBRD) in the 1950s. Also of note is the Federal Bureau of Investigation file on Hirschman that was requested by Jeremy Adelman in 2006 under the Freedom of Information Act. Annotations of the FBI file on Post-it notes are Adelman's.

Series 1: Articles, books, and lecture notes includes articles and books written by Lilienthal from 1918-1949 and lecture notes from Lilienthal's time at law school.

Series 2: Speeches consists of drafts and final versions of speeches given by Lilienthal.