Khalaf has written extensively on the Arab world and on Lebanon in particular.
[1] The majority of themes in his work include sexuality in the Arab world,[2] the Lebanese Civil War, Urbanization, and the role of the Protestant missionaries in the Levant.
Until 2017, he was a professor of sociology at the American University of Beirut, where he had also been a director of the Centre for Behavioural Research since 1994.
Khalaf received his bachelor's degree in Economics from the American University of Beirut in 1955, and later his MA in Sociology in 1957.
[3][4] He is married to Roseanne Khalaf with whom he co-authored Arab Youth in 2012.