Herbert S. Klein is the author of 22 books and 155 articles in several languages on Latin America and comparative themes in social and economic history. Among these books are The Middle Passage: Comparative Studies in the Atlantic Slave Trade (1978) and four studies of slavery, the most recent of which are Slavery and the Economy of So Paulo, 1750-1850 (co-author, 2003); African Slavery in Latin America and the Caribbean (co-author, 2008); and Slavery in Brazil (co-author, 2009), as well as four books on Bolivian history, including A Concise History of Bolivia (2003). He has also published books on such diverse themes as The American Finances of the Spanish Empire, 1680-1809 (1998), and A Population History of the United States (2004).