The reactions of users to each of the INSPEC services are being sought as part of the normal development of these services and through a series of user studies. It was the aim of this study to assess the respective roles of individual profile selective dissemination of information (SDI), standard profile SDI, current-awareness publications and abstract journals. The study was designed to compare the relative value and use made of each service and to investigate the circumstances under which Science Abstracts, Current Papers, TOPICS and SDI are most useful. The investigation commenced with a pilot study in which six subscribers to INSPEC services were requested to participate. Each subscriber was asked either to complete a questionnaire which was sent to him, or to take part in a structured interview based on the same questionnaire. The questions investigate the use made of abstract journals, current awarness publications, standard and individual profile SDI and their comparative value. Based on the responses, the use made of the services, the value to the subscriber, and the circumstances under which each is most useful are discussed. (Related studies are: LI 004105 and 004107) (Author/SJ)