It’s hard to find the full audio or video of the speech (it’s been locked up in litigation for years) but here is a link to the transcription of the speech text. Most people don’t realize that the title of the speech wasn’t in the original prepared text. It wasn’t until the famed Gospel singer Mahalia Jackson yelled out, “Tell ’em about the dream, Martin!” that the Reverend went off script and adlibbed much of the rest of the speech.

King speechwriter Clarence Jones realized what was happening when he saw King “push the text of his prepared remarks to one side,” he wrote in the Washington Post in 2011. “I leaned over and said to the person next to me, ‘These people out there today don’t know it yet, but they’re about ready to go to church.”