In this paper, we revisit the revolutionary principles-equity, social justice, and health for all; community participation; health promotion; appropriate use of resources; and intersectoral action-raised by the 1978 Alma-Ata Declaration, a historic event for health and primary health care. Old health challenges remain and new priorities have emerged (eg, HIV/AIDS, chronic diseases, and mental health), ensuring that the tenets of Alma-Ata remain relevant. We examine 30 years of changes in global policy to identify the lessons learned that are of relevance today, particularly for accelerated scale-up of primary health-care services necessary to achieve the Millennium Development Goals, the modern iteration of the "health for all" goals. Health has moved from under-investment, to single disease focus, and now to increased funding and multiple new initiatives. For primary health care, the debate of the past two decades focused on selective (or vertical) versus comprehensive (horizontal) delivery, but is now shifting towards combining the strengths of both approaches in health systems. Debates of community versus facility-based health care are starting to shift towards building integrated health systems. Achievement of high and equitable coverage of integrated primary health-care services requires consistent political and financial commitment, incremental implementation based on local epidemiology, use of data to direct priorities and assess progress, especially at district level, and effective linkages with communities and non-health sectors. Community participation and intersectoral engagement seem to be the weakest strands in primary health care. Burgeoning task lists for primary health-care workers require long-term human resource planning and better training and supportive supervision. Essential drugs policies have made an important contribution to primary health care, but other appropriate technology lags behind. Revitalisng Alma-Ata and learning from three decades of experience is crucial to reach the ambitious goal of health for all in all countries, both rich and poor.