Sentence types and word-order patterns in Arabic have been a matter of debate and controversy for a long period of time. They were hotly discussed by the medieval Arab grammarians and continue to be a major topic of discussion among modern scholars. This book describes the development of the medieval grammarians' theory of sentence types; a development from the theory of 'amal, which lies at the heart of medieval Arabic grammatical tradition. Each major topic is discussed with a view to explore the basic principles underlying the medieval grammarians' arguments. Special attention is given to conceptual problems arising from conflicts with the theory of 'amal. This is followed by an assessment of the contributions made by modern scholars to the analysis and description of the constructions involved. Modern Arabists and linguists are shown to have concentrated on word-order patterns rather than on sentence types, placing special emphasis on the functional aspects of word order variations in Arabic.