Insurance plays a positive role in economic develoment, but some of its traditional products are inhibiting in some cultural settings. This book explains the development of a hybrid model. Takaful (which means "cooperative") is intended to deal with three prohibited or haram practices under Islam: the payment of interest (riba), the existence of uncertainty in a stransaction (gharar), and gambling (maysir). The primary intent of this relatively recent entry to world insurance markets is to provide a core service to Muslims and others who have religious or ethical objections to conventional commercial insurance models. A secondary intent is to develop a model that deals with the capital challenges that have faced mutual insurers in the West and the subsequent decline of the mutual business model. Two realities -- the uneven approaches to takaful and the economic potential that its availability is releasing -- mean that it is especially important to facilitate debates that promote an understanding of takaful. This book, while not attempting to take on a role belonging to sharia lawyers and regulators in Islamic countries, provides a comprehensive overview of mutual insurance structures, including Christian and Jewish examples as well as other hybrid models, to provide a broad overview of the universe of operating models and present ideas for moving forward. It also explores avenues for further opportunities, including the application of takaful to microinsurance markets in emerging countries with large Muslim populations.