This paper examines the complex interconnections between the development of health promotion and multidisciplinary public health, respectively. Health promotion takes a distinctive interdisciplinary and multiprofessional perspective on health. Historically, it has brought together practitioners from varied disciplinary backgrounds, education and training. It therefore brings real advantages to the public health enterprise, where the goal is to bridge organisations, professions and partners to collectively address key determinants of health in the most effective manner. This paper debates the contribution health promotion has made to the development of multidisciplinary public health over the past 30 years and explores the principles, values, professional bases and practices of both. It is argued that health promotion's contribution to the development of 'the new public health' was critical, while its status and role within multidisciplinary public health remain problematic and unresolved. The nature of these dilemmas is discussed, reflecting on missed opportunities and possible resolutions. © 2007 The Royal Institute of Public Health.