Michael Cook's classic study, Commanding Right and Forbidding Wrong in Islamic Thought (Cambridge, 2001), reflected upon the Islamic injunction to forbid wrongdoing. This book is a short, accessible survey of the same material. Using Islamic history to illustrate his argument, Cook unravels the complexities of the subject by demonstrating how the past informs the present. At the book's core is an important message about the values of Islamic traditions and their relevance in the modern world.