Objectives: To describe a conceptual framework to assist in the application of capacity-building principles to public health nutrition practice. Design: A review of the literature and consideration of the determinants of effective public health nutrition practice has been used to inform the development of a conceptual framework for capacity building in the context of public health nutrition practice. Result: The limited literature supports a greater integration and application of capacity-building strategies and principles in public health nutrition practice, and that this application should be overt and strategic. A framework is proposed that identifies a number of determinants of capacity for effective public health nutrition action. The framework represents the key foundations for building capacity including leadership, resourcing and intelligence. Five key strategic domains supported by these foundation elements, including partnerships, organisational development, project management quality, workforce development and community development, are proposed. This framework can be used to assist the systematic assessment, development and evaluation of capacity-building activity within public health nutrition practice. Conclusions: Capacity building is a strategy within public health nutrition practice that needs to be central to public health nutrition intervention management. The present paper defines, contextualises and outlines a framework for integrating and making explicit the importance of capacity building within public health nutrition practice at many levels. Keywords Public health nutrition Capacity building PracticeDespite the development of public health nutrition (PHN) as a field of practice over the past few decades, little has been published to support an assessment of or describe what constitutes capacity building in PHN practice. A number of studies have attempted to describe self-reports of practice as part of workforce development research (1,2) and others have attempted to articulate the competency requirements for PHN practice that logically reflect the work required for effective practice (3,4) . A consistent finding from the present work has been practice-based activity that reflects a process of development, implementation and evaluation of population-level interventions as a core function and practice focus for public health nutritionists (5) , and an appreciation of the importance of building capacity to support action to address PHN issues. Each of these broad areas of practice is consistent across health promotion and broader public health effort. Consideration of capacity building as a practice concept (what, why and how?) for PHN therefore is needed.The present paper draws on a non-exhaustive review of scholarship in the published and grey literature from the disciplines of nutrition, public health and health promotion. This has been considered against the experience of the authors in practice to propose a conceptual framework for the application of capacity-building principle...