OBJECTIVE: To assess the feasibility, acceptability and fidelity of a feeding team intervention with an embedded randomised controlled trial of team-initiated (proactive) and woman-initiated (reactive) telephone support after hospital discharge. DESIGN: Participatory approach to the design and implementation of a pilot trial embedded within a before-and-after study, with mixed-method process evaluation. SETTING: A postnatal ward in Scotland. SAMPLE: Women initiating breast feeding and living in disadvantaged areas. METHODS: Quantitative data: telephone call log and workload diaries. Qualitative data: interviews with women (n=40) with follow-up (n=11) and staff (n=17); ward observations 2 weeks before and after the intervention; recorded telephone calls (n=16) and steering group meetings (n=9); trial case notes (n=69); open question in a telephone interview (n=372). The Framework approach to analysis was applied to mixed-method data. MAIN OUTCOME MEASURES: Quantitative: telephone call characteristics (number, frequency, duration); workload activity. Qualitative: experiences and perspectives of women and staff. RESULTS: A median of eight proactive calls per woman (n=35) with a median duration of 5 min occurred in the 14 days following hospital discharge. Only one of 34 control women initiated a call to the feeding team, with women undervaluing their own needs compared to others, and breast feeding as a reason to call. Proactive calls providing continuity of care increased women's confidence and were highly valued. Data demonstrated intervention fidelity for woman-centred care; however, observing an entire breast feed was not well implemented due to short hospital stays, ward routines and staff-team-woman communication issues. Staff pragmatically recognised that dedicated feeding teams help meet women's breastfeeding support needs in the context of overstretched and variable postnatal services. CONCLUSIONS: Implementing and integrating the FEeding Support Team (FEST) trial within routine postnatal care was feasible and acceptable to women and staff from a research and practice perspective and shows promise for addressing health inequalities. TRIAL REGISTRATION: ISRCTN27207603. The study protocol and final report is available on request.