Organized abolitionism had been in operation for nearly fifty years when it took a radical turn during the 1830s. “The time is now: The rise of immediate abolition” describes how a new generation of Anglo-American abolitionists made immediate emancipation the movement’s standard, spawning wide-ranging debates about abolitionist radicalism. Led by a diverse and multicultural constellation of activists, abolition’s second wave embraced a crusading brand of reform that refused to defer to slaveholders’ or politicians’ concerns. Experimenting with new tactics—from mail campaigns that bombarded slaveholders with antislavery literature to the physical defense of fugitive slaves—abolitionists became full-time activists and professional reformers. It was an explosive era of activism.