Andalusi Arabic is not only the Arabic dialect of which we have the earliest relatively extensive records providing basic information for the study of mainly, though not exclusively, Western Neo-Arabic, but also the spoken language of the Southern and for centuries most advanced half of the Iberian Peninsula, which had a considerable impact, most often not sufficiently gauged and surveyed by Western scholars, on the development of all kinds of Medieval and Modern culture and science. The present manual describes the different grammatical levels of this language, phonemics, morphology and syntax, in addition to the main features of its mixed lexicon and provides some text samples of diverse periods and locations, plus the usual indices and technical data. As the fourth survey of this nature by the same author since 1977, prompted by awareness of a certain lack of interest in a subject which was by no means exhausted and fully mastered, it contains the results of several decades of untiring endeavours and minute analysis of facts detected not only in Arabic records, but also hidden in the rich array of related witnesses hidden in the Romance languages of the Iberian Peninsula.