BACKGROUND: While the global prevalence of smoking during pregnancy is 1.7%, it rises to 8.1% in Europe, where it is the main modifiable risk factor for morbidity and mortality during pregnancy. However, pregnancy is a key time to implement smoking cessation interventions, as women are more likely to adopt health-promoting behaviours during this period. Despite the availability of resources (e.g. policies, tools) and strategies (e.g. nicotine replacement therapy) to address smoking, their implementation remains neither optimal nor systematic. To address this, a multi-disciplinary multi-professional team developed the 5A-QUIT-N intervention to promote smoking cessation in pregnant women, by mobilising health professionals and optimising existing resources. Rather than creating new resources, the intervention uses existing tools and strategies and better integrates them into the pregnancy monitoring process. This article describes the development and operationalisation of the 5A-QUIT-N intervention. METHODS: The development of the 5A-QUIT-N intervention involved three stages. First, its components were established according to national recommendations and a final list was validated by a scientific committee. Next, obstacles and levers that could influence their implementation and effectiveness were identified through a scoping review and semi-structured interviews. The resulting data were then used to design the first version of the intervention. RESULTS: Findings from the literature and field experiences highlighted the need for better mobilisation and coordination of the existing resources. The 5A-QUIT-N intervention was developed to address these issues by improving resource organisation within each region. At the clinical level, it aims to enhance healthcare professionals' skills in smoking cessation practices using existing resources. At the organisational level, it promotes closer coordination between perinatal and smoking cessation professionals. The involvement of local stakeholders and local resources is an integral part of the intervention, as these vary from one region to another. CONCLUSION: This intervention was made possible thanks to the combination of a literature search, a qualitative study, and commitment from stakeholders from grassroots level upwards.< Leer menos