The Arabic grammatical tradition is one of the great traditions in the history of linguistics, yet it is also one that is comparatively unknown to modern western linguistics. The purpose of the present book is to provide an introduction to this grammatical tradition not merely by summarizing it, but by putting it into a perspective that will make it accessible to any linguist trained in the western tradition. The reader should not by put off by the word 'medieval': Arabic grammatical theory shares a number of fundamental similarities with modern linguistic theory. Indeed, one might argue that one reason Arabic theory has gone unappreciated for so long is that nothing like it existed in the West at the time of its 'discovery' by Europeans in the 19th century, when the European orientalist tradition was formed, and that it it only with the development of a Saussurean and Bloomfieldian structural tradition that a better perspective has become possible.