Leak provides a survey of Islam, and its relations to Christendom. His work involves the history, distribution, doctrines, and practice of Islam, and argues that the utter unlikeness of Allah is equivalent to agnosticism. He explores the social ideal of Islam, and its social practice, with emphasis on the unpleasant position of women. Contacts between Christianity and Islam are briefly mentioned in his recapitulation of al-Kindi, Francis of Assisi and Francis Xavier; the history leaps from Lull in the thirteenth century, to Martyn in 1806, to Pfander and the literally short-lived efforts of Valpy French and Keith Falconer. Methods of Christian approach, not all for professed missionaries, speaks of evangelism, medical work, women's work, educational work, literature and approaches to children. Leak proclaims the successes in Egypt, Afghanistan, and Indonesia, and adds an appendix on changes since the Great War. This is a useful background to any student of Christian missionary work - or the reaction to it.