The attitudes and behaviours of academics from different disciplines towards depositing their work in institutional repositories are compared. This is achieved through the use of a survey strategy, and by examination of the contents of a twenty-five UK institutional repositories. The survey targets humanities academics, and the data is compared to that from previous surveys focusing on scientific, technical and medical (STM) disciplines. The number of humanities documents in institutional repositories is currently far lower than that in STM disciplines. Awareness of Open Access amongst humanities academics is also low. However they perceive many advantages to depositing their work in institutional repositories, especially for the reader, not for themselves. Around two-thirds of respondents would deposit work in institutional repositories, despite having several concerns. Those who would not deposit work in this way perceive the same disadvantages: potential for plagiarism, the apprehension of interfering with publishing their work elsewhere, and the fragility of online means of dissemination. Increased depositing in institutional repositories in the future depends on encouraging authors of the advantages of doing so, not only to others but also to themselves. At this early stage of development understanding the attitudes of academics in different disciplines is crucial.