Ismaili and Other Arabic Manuscripts is a supplement to Adam Gacek's two-volume Catalogue of Arabic Manuscripts in the Library of the Institute of Ismaili Studies, published in London, 1984-1985. This new catalogue includes 189 Arabic manuscripts not listed earlier by Gacek or which have been acquired since then by the Institute of Ismaili Studies Library. The majority of the works belong to the theological, philosophical and historical traditions of Fatimid and post-Fatimid Yemeni Ismaili literature, including manuscripts by important and hitherto unknown authors from Syria. The catalogue is arranged alphabetically by author and chronologically by title and provides details of the content of each work and other relevant information of a literary, historical and doctrinal nature. There are references to other catalogues listing the same works to be found in other collections, followed by details of the main editions, translations and studies. Ismaili and Other Arabic Manuscripts is fully illustrated with colour photographs of selected manuscripts.