The increase in overweight and obesity among children has emerged as an important public health issue. This trend has highlighted the need for accessible and novel approaches to support healthy weights for children and their families to prevent childhood obesity. The purpose of this article is to describe the iterative development and scale-up of a community-led, national-level project to promote healthy weights among Canadian children and families who may be experiencing vulnerabilities. In this project, the Healthy Together program was designed to engage families in an interactive program to support healthy lifestyles. The program also provides a platform for creating supportive environments for healthful lifestyles through practice and policy change. Based on a process evaluation, we describe the iterative development of Healthy Together from Phase 1 through 3 to shed light on processes shaping implementation and scale-up of the program. Lessons learned during each phase were used to refine the program and further expansion. Indicators of successful scale-up include the Healthy Together program’s cross-jurisdictional reach and promising evaluation results in real-world conditions. The practice-based program scaling approach provides practical guidance for planning and implementing similar health promotion programs in diverse communities.

儿童超重和肥胖的增加已成为一个重要的公共卫生问题。这一趋势凸显了需要采用可访问的新方法来支持儿童及其家庭的健康体重，以防止儿童肥胖。本文的目的是描述一个社区主导的国家级项目的迭代开发和扩大规模，以促进可能面临脆弱性的加拿大儿童和家庭的健康体重。在这个项目中，Healthy Together 计划旨在让家庭参与互动计划，以支持健康的生活方式。该计划还提供了一个平台，通过实践和政策变化为健康的生活方式创造支持性环境。基于过程评估，我们描述了 Healthy Together 从第 1 阶段到第 3 阶段的迭代开发，以阐明影响该计划实施和扩大规模的过程。在每个阶段学到的经验教训都被用来改进计划和进一步扩展。成功扩大规模的指标包括 Healthy Together 计划的跨辖区影响力和在现实世界条件下有希望的评估结果。基于实践的计划扩展方法为在不同社区规划和实施类似的健康促进计划提供了实用指导。成功扩大规模的指标包括 Healthy Together 计划的跨辖区影响力和在现实世界条件下有希望的评估结果。基于实践的计划扩展方法为在不同社区规划和实施类似的健康促进计划提供了实用指导。成功扩大规模的指标包括 Healthy Together 计划的跨辖区影响力和在现实世界条件下有希望的评估结果。基于实践的计划扩展方法为在不同社区规划和实施类似的健康促进计划提供了实用指导。