ISSUE ADDRESSED: One in four Australian children aged between the ages of two and four are affected by overweight. In New South Wales, the Communicating Healthy Beginnings Advice by Telephone (CHAT) trial delivered an intervention to pregnant women and women with infants via telephone calls and text messages. The focus of the intervention was on infant feeding and establishing healthy habits for infants by building the capacity of mothers. This study investigates trial collaborators' perspectives concerning the implementation of this intervention, to obtain insights that will support future translation and scale-up. METHODS: This research was undertaken during the intervention phase of the trial. Twenty trial collaborators involved in the planning, implementation or delivery of the CHAT trial were invited to participate. Qualitative interviews were conducted with collaborators using open-ended questions based on Steckler and Linnan's process evaluation framework and the Consolidated Framework for Implementation Research. Inductive thematic analysis was employed to identify themes from the interview data. RESULTS: Fourteen trial collaborators were interviewed. Collaborators included child and family health nurses (intervention providers), nurse managers with extensive child and family health nursing experience, a paediatrician, dietitians, health promotion experts, health service managers, health and nursing executives, program personnel (project coordinator, research fellow and evaluation officer) and university researchers. Following coding of qualitative data, themes were realised from the data as a result of active co-production on the part of the researcher. Five themes were identified: (a) context (organisational support, engagement and partnerships, communication and project leadership); (b) program receipt, benefit and reach; (c) program delivery (intervention providers' experience and skills, mode of intervention delivery, referral to other services, support and training for intervention providers); (d) implementation (program delivered as planned); (e) opportunities for scale-up. Collaborators perceived that the program was implemented and delivered as planned. This specific research addresses the success of the process of implementing and delivering interventions for infant feeding and establishing healthy habits for children by building the capacity of mothers. Collaborators attributed successful program implementation to contextual factors: strong support by the host organisation; good project leadership; clear communication; collaborative internal and external partnerships; intervention provision by experienced nurses. Remote delivery was convenient to program participants and participants were able to resolve other personal concerns in addition to direct immediate benefits. Because of their capacity to influence policy decisions, the absence of policymakers at project meetings was a shortcoming. Collaborative partnerships with health and research partners, understanding of contextual issues and consumer involvement could lead to program expansion. The program has the potential to be scaled up through integration with existing services and gradual expansion into other health districts prior to state-wide rollout. CONCLUSIONS: The CHAT trial delivered the Healthy Beginnings intervention which resulted in improvements in infant feeding, active play and sedentary behaviours. This evaluation demonstrated that the involvement of key stakeholders from early planning stages through to implementation of the program and the partnerships that evolved contributed to the successful implementation of the program. An unintended benefit to participants from this program was the social support that was provided. Intervention delivery via telephone and text messages enabled easy access to the program. Most importantly, the program has the potential to be scaled up through integration into existing services and gradual expansion prior to state-wide rollout. SO WHAT?: Strong internal and external partnerships, effective communication systems and integration with existing services create the context for potential translation and scaling up of the program to other health promotion settings.