Peter Singer made animal rights an international concern in 1975 when he published Animal Liberation, an instant classic depicting the shocking and widespread abuse of animals. Thirty years later, Singer reflects upon changes and new challenges by bringing together specially commissioned essays by philosophers and activists, chronicling current thoughts on animal suffering, reassessing the question of personhood, and highlighting tales of effective advocacy. In addition, he details 'Ten Tips for Activists', taking the reader beyond ethical theory and into the day-to-day campaigns for animal rights. Long hailed as a brilliant and controversial philosopher, Singer has assembled incisive new articles sure to rouse and inspire all who believe in the rights of animals.