The present study attempted to measure the overlap of tasks being performed by Librarians Class One and Library Technicians Grades Two and Three in special libraries located in Commonwealth Government Departments and Statutory Authorities in the ACT. Overlap was also measured between the two groups in libraries with six or more staff, since size of library could have affected the results; and between graduates (those employees with university or college of advanced education degrees or graduate diplomas in library and information science), and nongraduates (those without such qualifications). To measure the overlap, a task list questionnaire was devised based on task lists utilised in other research studies or which had been the outcome of professional workshops. Work level guidelines and position classification standards developed by pertinent Australian employing authorities and the Library Association of Australia were also used. Results suggested that there may be considerable overlap in work being performed by Librarians Class One and Library Technicians Grades Two and Three in the nominated libraries. Of the eight functional areas of library work into which the task list questionnaire was divided, only two areas, Reference, and Current Awareness and User Services, resulted in proportions of the groups tested being assigned the tasks in significantly different proportions. For the six other functional areas, representing 125 of the 160 tasks Librarians Class One and Library Technicians Grades Two and Three performed the same tasks in similar proportions. Testing for size of library and qualifications of respondents made very little difference to these results. Conclusions drawn from the present study are limited because the questionnaire ignored the level of importance and the time occupied in completing these tasks. Other constraints occurred in relation to conclusions which could be made. The questionnaire methodology as utilised by the present study is more likely to evoke responses to what is there; and it does not identify what should be done or how well tasks are performed. The study is limited to special libraries within Commonwealth Government Departments and Statutory Authorities and is confined to three levels of staff only, Librarians Class One and Library Technicians Grades Two and Three. Despite these limitations, it seems clear that the levels of staff included in the present study are often assigned tasks on the basis of what tasks have to be done, rather than with regard to matching level of task to level of position within the boundaries of the work level guidelines; and this situation is also true of the larger libraries with six or more staff. These results have implications for those involved in educating professional librarians and library technicians, for the interpretation given by the profession to the meaning of professionalism and for staff relations between librarians and library technicians. Debate by the profession concerning the roles of librarians and library technicians is an issue demanding urgent attention.