Early research on Ismaili Shii works among the vast corpus of medieval Islamic knowledge production yielded important bibliographies by Wladimir Ivanow and Ismail Poonawala. These bibliographies demonstrated the central role played by Ismaili Shiis during the 9-12th centuries in contributing to the efflorescence of Islam. The bibliographies also indicate the degree to which Ismaili Shii works formed part of the knowledge consumed by non-Ismaili Muslims during this period. A case in point would be the wide circulation of the Rasa’il Ikhwan al-Safa among various groups within and beyond Muslim communities and schools of thought, over a wide geographic range. What has been less examined however, are the private collections of Ismaili Shiis. Leaving aside the official libraries of rulers such as the Fatimids (although even here, as Paul Walker has demonstrated in his research on Fatimid-era learning, we can only speculate the range of the dynasts’ collection), there were the private collections of individual Ismaili scholars and intellectuals. Drawing on the work of Nelly Hanna, who examined such collections in the much later period of late medieval Ottoman Egypt in an effort to investigate the interests of wealthier individuals of that time and place, this paper will review catalogues of two private collections now housed at the Institute of Ismaili Studies in London, namely the Hamdani and Zahid Ali collections (whose provenance reaches back into the late Fatimid period), in an effort to understand what they reflect of the interests of Ismaili scholars. The paper will ask if these collections were limited to confessional or doctrinal texts. If not, what role did non-Ismaili works in these collections play in the outlook and identities of these scholars? Did they intersect with the concerns and identities of non-Ismailis of the same time period? And what can we say about the transmission of knowledge in the informal and private efforts and activities of such scholars. In so doing, this paper suggests a fuller and more nuanced understanding of the social and cultural capital these collections bestowed on their owners and a better understanding of their role in the larger Muslim intellectual community.