The author begins with a fact to be urgently reckoned with: Islam as a universal religion is currently spread across the five continents numbering, in its various forms, about 1 billion believers. After a few centuries during which religion seemed to be declining and the phenomenon of secularisation was considered one of the features of modernity, an attentive observation of social reality reminds us of C. Dawson's words: "the development of scientific specialisation in no way reduces the human need for a historical faith'. Presented in interview form, this slim volume allows the reader to approach the complexity of the phenomenon of Islam without claiming to be exhaustive. The experience of the author, who lived the first twenty years of his life in Morocco and who has visited other Northern African and Middle-Eastern countries guarantees an understanding of Islam that other writers do not possess. The expansion of Islam was remarkably easy from its outset: beside Mohammed's will to publicly preach his doctrine there was his interest in setting up a community (Umma). The simplicity of the Islamic doctrine and law together with its totalising nature favoured an easy adhesion to it. Where the Christian culture was dissolving the Muslims did not force conversion. Wherever they passed and from the initial period of their settlement many of them displayed a great curiosity towards their surroundings and a desire to learn. All this is presented in the book whilst avoiding that naive apology of Islam so frequently found nowadays.