The consultant nurse (CN) role is usually described in terms of four domains devised by the Department of Health - clinical practice, education and training, leadership, and research and service development. This study set out to explicate the diversity and complexity of CN roles in an NHS trust; to describe aspects of extraordinary practice and to identify perceived differences between this role and other advanced practice roles. Accounts were written by six CNs and subjected to concept mapping to facilitate identification of extraordinary practice. Four themes emerged: entrepreneurial activity and innovation; clinical autonomy and role dynamism; influential national and international research conduct; consultancy and education across discipline boundaries. These included descriptions of higher order skills that surpass usual requirements of 'expert' or 'advanced' practice. Comparisons with other advanced practice roles are drawn from the literature and data collected in this study. Differences between the roles have implications for sustainability.