To assess and develop consensus among experienced public health nutrition practitioners from high-income countries regarding conceptualisation of capacity building in practice, and to test the content validity of a previously published conceptual framework for capacity building in public health nutrition practice.

A Delphi study involving three iterations of email-delivered questionnaires testing a range of capacity determinants derived from the literature. Consensus was set at >50 % of panellists ranking items as ‘very important’ on a five-point Likert scale across three survey rounds.

Public health nutrition practice in Australia, the UK, Canada and the USA.

Public health nutrition practitioners and academics.

A total of thirty expert panellists (68 % of an initial panel of forty-four participants) completed all three rounds of Delphi questionnaires. Consensus identified determinants of capacity building in practice including partnerships, resourcing, community development, leadership, workforce development, intelligence and quality of project management.

The findings from the study suggest there is broad agreement among public health nutritionists from high-income countries about how they conceptualise capacity building in public health nutrition practice. This agreement suggests considerable content validity for a capacity building conceptual framework proposed by Baillie et al. (Public Health Nutr 12, 1031–1038). More research is needed to apply the conceptual framework to the implementation and evaluation of strategies that enhance the practice of capacity building approaches by public health nutrition professionals.