AIM: This paper reports the findings from a naturalistic enquiry undertaken in the United Kingdom into the extent to which the ideals and values of the preregistration nursing course are adopted by individual newly educated Registered Nurses. BACKGROUND: Research in several countries provides consistent evidence of the existence of a theory-practice gap in nursing. Clear disparities have been demonstrated between the best practice ideals and values that are taught and those actually encountered in everyday practice. Nurse education 'Project 2000' reforms in the United Kingdom were designed, in part, to address this issue. Few studies to date have examined the impact of these reforms on newly qualified Registered Nurses' ability to translate theory into practice. METHODS: A longitudinal study was carried out in three educational institutions in the United Kingdom from 1997 to 2000. Final year nursing students (n = 72) in three colleges of nursing completed questionnaires to elicit views on their ideals and values for practice. In-depth interviews with a purposive subsample of 26 participants (at 4-6 and 11-15 months postqualification) indicated the extent to which these ideals and values were adopted in practice. Interviews were tape-recorded, transcribed, and data were analysed using constant comparison and negative case analysis. FINDINGS: Although new nurses emerged from their programmes with a strong set of nursing values, a number of professional and organizational factors effectively sabotaged implementation. Professional sabotage includes obeying covert rules, lack of support and poor nursing role models. Organizational sabotage includes structural and organizational constraints such as time pressures, role constraints, staff shortages and work overload. CONCLUSION: The disparity between nursing as taught and as practised may have profound implications for the future of the profession both in the United Kingdom and internationally, in terms of morale, job satisfaction and retention. Measures to improve resources and reduce the professional-bureaucratic work conflict are discussed.