The mental health of mothers is of significant concern to community practitioners. This paper reports on a case study exploring the success factors of a well established, health visitor-led protocol to identify and treat women with mild to moderate depression. Data were collected through interviews with a purposive sample of 12 community practitioners, a focus group of four health visitors and observation of a multidisciplinary steering group meeting. The protocol was described as an evidence-based tool and safety net that could be used flexibly to support clinical judgments and tailored to individual needs. Success factors included frontline clinician engagement and ownership, continuity of leadership to drive development and maintain momentum, comprehensive and on-going staff training, and strategic support for the protocol as a quality indicator at a time of organisational change. Quality and clinical leadership are continuing policy priorities. The protocol enabled frontline staff to lead a service innovation, providing a standardised multiprofessional approach to women's mental health needs through effective support, advice and treatment that can be measured and quality assured.