In the wake of the shooting death of nine African-American churchgoers in Charlestown, South Carolina, many politicians and public figures called for a public conversation on race and racism.
But for activists, educators, historians and others, the conversation has been going on for decades.
"Tired of having one-sided conversations. We need people to read a book and educate themselves," wrote Chad Williams, an associate professor and chair of the African and Afro-American Studies Department at Brandeis University.
It was Williams and his colleagues who spearheaded #CharlestonSyllabus, a hashtag devoted to recommending books required for those who wanted to understand race and racism in the US.
The tag was inspired by a similar project after Michael Brown was shot in Ferguson, Missouri.
More than 15,000 have used the tag in the past week. Librarians have volunteered to curate the list; teachers are turning to it to help plan lessons.
The BBC asked some active contributors to the hashtag what book they recommended, and why.
Do you have a book you'd add to the #CharlestonSyllabus? Tweet it to us at @BBCTrending.
Video by Elena Boffetta