This paper describes a new classification of ward organizational practice in nursing. Data related to aspects of ward nursing practice were collected by postal survey from a nationally representative sample of 74 acute hospital wards, and subjected to hierarchical cluster analysis. The model which was deemed to best 'fit' the data, provided three types of ward practices, which have been named: 'devolved', 'two tier' and 'centralized' nursing. The distinguishing features of the three classifications are similar but not identical to accepted 'ideal types' of primary, team and functional systems. The relationships between wards in each of the three identified categories and other ward organizational practice processes of nursing care and job satisfaction are described.