Although the Sultanate of Oman’s Ministry of Heritage and Culture has published many classics of Ibāḍī scholarship and small bookstores like Maktabat al-Ḍāmirī and Maktabat al-Istiqāma have also contributed many valuable publications, much Ibāḍī scholarship remains unpublished. This paper will describe the major archival sources of Ibāḍī manuscripts in Oman and Zanzibar, and will discuss the following: the types of Ibāḍī manuscripts found in various archives and libraries; what those contents tell us about Ibāḍī scholarship and readership in Oman and Zanzibar in the nineteenth and twentieth centuries; the extent to which and manner in which these manuscripts have been catalogued; the state of preservation and digitalization of the manuscripts; and the manuscripts’ accessibility to researchers and conditions of research. On this subject, Oman and Zanzibar have some points of comparability, such as the existence of private, uncatalogued collections, but there are also important points of contrast: whereas the Sultanate of Oman has a major interest in specifically Ibāḍī scholarship, for the people of East Africa Ibāḍīs, who were all of Omani descent, were often seen as foreigners, sometimes admired and sometimes hated. Arabic manuscripts, which had undoubtedly already suffered from humidity and insects, were torn apart by angry revolutionaries in the Zanzibar revolution of 1964; the remnants were boxed and hidden away in the recesses of the Zanzibar National Archives, where for years the staff insisted that they had no Arabic manuscripts. Whereas Oman has had the financial wherewithal to invest in manuscript preservation and digitalization, Zanzibar has not. Nonetheless, there are significant things to be learned from these manuscripts, including the interest that Ibāḍīs in Zanzibar had in Sunni literature, as is evident from the presence of many Sunni texts in Ibāḍī-owned waqfs. Texts by Ibāḍī scholars resident in Zanzibar in the nineteenth and early twentieth centuries indicate a broad range of scholarship, including works on Ibāḍī fiqh and theology, local herbal medicine, and a refutation of the ninth-century Nestorian Christian work known as The Apology of al-Kindi. Copies of books and manuscripts from Oman and other Arab countries may also be found. The Zanzibar Sultanate established a printing press in 1879 and published works by Ibāḍī scholars in Oman and Algeria, as well as one by a Zanzibari scholar.