Synopsis This little book has been composed in order to present to the English-reading public, Muslim as well as non-Muslim, the viewpoint of orthodox Islam with regard to Hadith literature, its origin and development, and its criticism by the Muslim doctors. For in English, only one book on the subject has been published (The Traditions of Islam by Alfred Guillaume, Oxford, 1924). But is does not represent the Muslim point of view. In other European languages (like German, French and Dutch) several highly learned and critical works on Hadith have been published. But none of them represents orthodox Islamic views. This book was begun in 1930 and was almost completed in 1936. In composing it, not only many of the important works of the modern European orientalists have been utilized but also a large part of the original Arabic sources, some of which (so far as I know) have not hither to been fully utilized. The reader, therefore, may find in this work some important material which may not be available in any of the European works on the subject.