WATERVILLE — Douglas Foster, Northwestern School of Journalism, will speak on Voices of Young South Africans: Freedom in a Post-Transitional Democracy at 7 p.m. Thursday in Olin 1, at Colby College.

Foster will discuss his recent book, “After Mandela: The Struggle for Freedom in Post Apartheid South Africa,” focusing on the role of youth in a society in which 40 percent of the population is under 18 years of age.