A collection of manuscripts is of little value unless it is accompanied by a comprehensive catalogue. From its inception the policy of the IMHM has been to supply catalogue cards for all its manuscripts as soon as possible after their acquisition. Complete descriptions of manuscripts listing all bibliographical, codicological and palaeographic information is an exhaustive and time consuming task. If the IMHM were to describe its manuscripts in this manner the project would take decades to complete and, in the meantime, the great majority of the Institute's holdings would remain uncatalgued. For this reason the policy of the IMHM during its first years was to prepare brief preliminary descriptions on catalogue cards and thus ensure that the great majority of its manuscripts would be retrievable for research. During these first years when thousands of films arrived annually the only method of supplying descriptions for each manuscript was to copy information from printed catalogues onto file cards. Only those manuscripts that had never been described previously were studied and catalogued from the microfilms. Since the Institute moved to the Jewish National and University Library in 1963, almost all the descriptions are based on perusal of the filmed manuscripts and not on printed catalogues alone.
The catalogue cards prepared until 1965 were very brief. They included only the author, title, subject, date and library and microfilm numbers. In 1965 the method of cataloguing was revised. More information was added to the cards: folio numbers, type of script, colophons, owner's entries and bibliographical notes. Cards were for the most part no longer reproduced manually by typewriter but by reprographic methods. This form of cataloguing continued for twenty years until, in 1986, a version of the ALEPH computer cataloguing program developed at the Hebrew University for use in the Jewish National Library was modified to suit the needs of the IMHM and the Manuscript Department.
Since the end of 1986 the card-catalogues have been closed and all cataloguing has been done by computer using the ALEPH system. The entire card catalogue has been converted to the computerized catalogue.