Waterlow's (1981) Sixth Boyd Orr Lecture on a ‘crisis of identity for nutrition’ stimulated the Nutrition Society's drive to professionalisation. Twenty-five years on, the Society begins a new stage; first, towards an independent voluntary regulator, and then towards statutory regulation. It is timely to reflect on progress and identify the remaining challenges. The Society has made impressive progress as a voluntary regulator since 1991 when the Insitute of Biology opened a register in cooperation with the Institute of Food Science and Technology and the Nutrition Society; the present register is 2·75-fold larger. The Society has specialist standards for course accreditation that enable graduates to apply for direct entry to the register, having met standards of competency in nutrition or public health nutrition. A code of ethics and a statement of professional conduct underpin a functioning system for oversight and governance that protects the public, the hallmark of all professions. Registered nutritionists lay easy claim to a unique science basis for their profession. A scheme for continuing professional development (CPD) started in July 2006, 1 year before a sample audit starts to show the link between CPD and re-registration. The scheme will be piloted in the first year. The critical challenge is the issue of identity. Waterlow (1981) stated that professional registration must lead explicitly and formally to a specific vocation, an occupation that provides services that society requires and one that contributes to the well-being and health of all. The present time may be the last and best chance for nutritionists, as nutrition has a higher priority for government in the UK than ever before. The Society has begun to help in strategic public health workforce planning and development; new and still plastic, it is the ideal locus from which a discipline and a profession can emerge. The CPD scheme will work if it helps nutritionists meet their own needs; more mutual cooperation and consensus about real world standards of performance are needed. Nutritionists need to show how they actually contribute to national health and/or wealth. Then, sustained resources can be advocated for and the support of the voting public and legislators secured, without which it will not be possible to get the legal protection that is desirable for the profession.