This thesis is concerned with hospital information systems. The literature relating to management information systems is examined in conjunction with the literature which specifically focuses upon hospital and nursing information systems. A field study, using a case study approach, is designed and implemented, its purpose being to analyse five sub-systems of a current hospital information system in use in one Hospital Board. This field study utilises a basic systems analysis methodology focusing upon the problem identification and performance identifications of the analysis cycle. In the problem identification phase forty-two subjects are interviewed, (83.3% of the sample being nurses in management positions). Check lists designed to test the sub-systems abilities to generate, store, retrieve and utilise data, and test the subjects knowledge of the sub-systems are devised and applied. The data obtained from the application of check lists is analysed and data flow charts and in-depth interview schedules developed for use in phase two or the performance identification phase of the field study. In phase two (performance identification) eleven subjects in administrative positions within the Hospital Board are interviewed using the data flow charts and the in-depth interview schedules as tools for eliciting data. Contrary to the author's expectations the field study results reveal a considerable diversity. In phase one the respondents possessed a sound knowledge of the admission/discharge, patient care and nursing management sub-systems. 85,7% of the nurse respondents have knowledge of the patient care sub-system and a further 79.2% have some knowledge of its ability to generate, store, retrieve and utilise information. In common with the administrators the high level of knowledge of retrieval and utlisation (89.2%) would indicate frequent use of the system. By contrast only 5.4% of the respondents in phase one had knowledge of retrieval and utilisation of the staffing information sub-system as compared with 100% in the administrators group. This same pattern emerges for the financial sub-system with 13.5% of the respondents having knowledge of retrieval and 18.9% of utilisation of the sub-system compared with 81.8% of administrators. These results indicate to the author that information systems development tends to be associated with each health discipline rather than with the macro development of a relevant, comprehensive hospital information system. To this end a series of questions are raised and possible answers provided. Finally a model which could become a prescription for future development is presented.