A major transformation has been occurring in primary health care during the past 20 years. The changes are reviewed briefly for the benefit of those who do not work in the front-line of care and for those who have not had the opportunity to experience the changes. Two major components of the transformation are stressed: (i) the shift towards person (patient) centred methods; (ii) a broad framework of reference which encourages horizontal integration of skills in the nonspecialized way. The opportunities for health promotion in primary health care are legion and evidence from worldwide experimental sources is reviewed to show how different levels of achievement can be demonstrated and monitored. Responsibility, empowerment and participation were firmly declared principles in the WHO Alma Ata Declaration on primary health care. The practical realisation of such principles in the field is occurring at an increasing rate, but their continuation will depend on the further growth and development of appropriate community-centred skills and practices. Evidence for the power of a "social sieve" to moderate professional or official health recommendations is also discussed in the light of current research. If recent research data is upheld, the relationship between primary health care personnel and the social network around them is likely to be shown to make a critical difference to health outcomes.