Systematic evaluation is an integral part of the organisation and delivery of community oral health care programmes, ensuring the effectiveness of these community-based interventions. As for general health promotion programmes the common problems from effectiveness reviews of oral health interventions relate to the quality and validity of programme evaluations. Problems identified mostly refer to the quality of outcome measures, short-term timescales to assess change, inadequate evaluation methodologies and inappropriate evaluation of programme implementation and processes. It remains a challenge to oral health professionals to integrate community oral health programmes into a wider health agenda. Public health research focusing on the development of evaluation methodologies has identified a variety of issues including the importance of using pluralistic evaluation approaches (quantitative and/or qualitative), limitations of the randomised controlled trial (RCT) design for evaluation of public health interventions, the need to match evaluation methods with the nature of intervention, development of outcome measures appropriate for the nature of intervention, importance of developing workforce capacity in evaluation techniques, and the need for development of partnerships between health practitioners and academics in conducting evaluations. In June 2003, the WHO Oral Health Programme at Headquarters organised a two-day workshop to take forward the development and documentation of the evaluation of oral health promotion and oral disease prevention programmes. The aims of the workshop were to: (1) identify common problems and challenges in evaluating community-based oral health interventions; (2) explore developments in the evaluation approaches in public health; (3) share experiences in evaluating oral health intervention programmes implemented at national or community levels in developing and developed countries and (4) develop guidelines for quality evaluation of national and community oral health programmes. Twenty-two invitees from 15 countries attended in addition to WHO staff. The first day was devoted to presentations of oral health promotion and oral disease prevention programmes from around the world. During the second day, WHO staff at Headquarters in Geneva discussed aspects of evaluation of public health programmes. Two working groups were formed to discuss agreed topics, and the reports from their deliberations, together with the general discussion, resulted in the presentation of emerging key issues and recommendations. In summary, it was agreed that evaluation of oral health promotion and disease prevention programmes should integrate, whenever possible, with general health programmes. While the design and advantages of RCTs in clinical evaluations are well documented, the relevance of this design in evaluation of community oral disease preventive programmes and oral health promotion programmes are much less clearly defined. Subsequently, the conduct of such programmes may be inappropriately evaluated in systematic reviews. There is a need for more research into appropriate immediate, interim and ultimate outcome measures, as well as process evaluation, an assessment that is poorly understood and practised less often than outcome evaluation. Guidance on potential design, conduct, and especially the evaluation, of community oral disease prevention programmes and oral health promotion programmes should be developed and updated regularly. WHO Collaborating Centres could have a role in promoting good practice, training and collaboration between teams throughout the world. Centres undertaking systematic reviews should consider the guidelines given in the proposed WHO document when defining their evaluation criteria.