Data relating to patterns of nursing activity and all the interactions occurring between patients and nursing staff were obtained during observation periods of 1 week's duration on a total of 20 wards in three hospitals. When analysed these data reveal that in all wards there is a strong relationship between the nursing hours available and the various components of the nursing care provided. Indeed the linear relationship is so strong in some cases that it appears that these wards are a long way short of the staffing levels which produced the ‘saturation’ effect described by several American authors. The analysis of the interactions reveals, as one would suspect, that a disproportionate number of patients account for a large proportion of the interactions, but two further analyses will, it is hoped, shed a little more light on this aspect of the ward situation. The data are being subject to further examination to ascertain whether extra nursing staff leads to more or longer interactions and a longer term investigation is under way which is focused on patients with comparable diagnoses in different hospitals.