Hizb ut-Tahrir al-Islami is an Islamist political party that wants to rule the world. It was founded by Taqiuddin an-Nabhani, a Palestinian Islamic jurist, in Jerusalem in 1952. Unlike al-Qaeda, it forswears violence, and unlike virtually all other Islamist parties, it refuses to participate in elections, because it believes democracy violates Islam. A group with such high ambitions and narrow operating constraints should have died out decades ago. But Hizb ut-Tahrir has not died out. It has grown. This book is about that surprising fact. The party''s presence in more than 40 countries exposes it to a wide range of political conditions, giving it a tactical flexibility many of its competitors lack. A new, globally aware class of young knowledge workers dominates its organizational culture and helps drive party growth even in the face of significant obstacles to its goal of reviving the caliphate.