Our objectives were to explore the perspectives of a community-based sample of Canadian parents with 2-5-year-old children on: (i) strategies to support the development of healthful weight-related behaviours and (ii) assessment approaches to measure weight-related behaviours and outcomes among children and families. We conducted 4 focus groups with 28 parents (89% mothers and 68% identified as White). Transcripts were analyzed using conventional content analysis. Regarding parent's perceptions of strategies to support healthful behaviours, we found that parents largely valued: home-based interventions, expert opinion, practical health behaviour strategies delivered in a nonjudgmental manner, and opportunities for social support. Regarding perceptions of assessment procedures, parents had mixed views on children providing blood samples, but looked upon it more favourably if it would contribute to research on child health. Our results suggest that to increase parental engagement interventions focused on improving weight-related behaviours among families with young children should be delivered within the home and include easy-to-implement behaviour change strategies communicated by experts, such as dietitians working in the clinical or public health setting. Using social media to share information and provide a platform for social support may also be an effective way to engage parents of young children.