An uncontrolled study with process evaluation was conducted in three U.K. community maternity sites to establish the feasibility and acceptability of delivering a novel breastfeeding peer‐support intervention informed by motivational interviewing (MI; Mam‐Kind). Peer‐supporters were trained to deliver the Mam‐Kind intervention that provided intensive one‐to‐one peer‐support, including (a) antenatal contact, (b) face‐to‐face contact within 48 hr of birth, (c) proactive (peer‐supporter led) alternate day contact for 2 weeks after birth, and (d) mother‐led contact for a further 6 weeks. Peer‐supporters completed structured diaries and audio‐recorded face‐to‐face sessions with mothers. Semistructured interviews were conducted with a purposive s...