Relatively few studies published so far look at the extent to which librarians communicate with each other. In particular, there has been little attempt to compare communication activities in different sectors of the profession. The results of a questionnaire and interview survey which examined the communication habits of library professionals in public, academic and special libraries and the national library are presented. The results show a very high level of communication in all sectors, although communication between sectors is more restricted. Overall, the similarities between the sectors are more striking than the differences.