OBJECTIVE: To assess the effect of a Crew Resource Management (CRM) intervention specifically designed to improve teamwork and communication skills in a multidisciplinary obstetrical setting. METHOD: Design--A before-and-after cross-sectional study designed to assess participants' satisfaction, learning and change in behaviour, according to Kirkpatrick's evaluation framework for training programmes. Setting--Labour and delivery units of a large university-affiliated hospital. Participants--Two hundred and thirty nine midwives, nurses, physicians and technicians from the department of anaesthesia, obstetrics and paediatrics. Intervention--All participants took part in a CRM-based training programme specifically designed to improve teamwork and communication skills. Principal measures of outcome-We assessed participants' satisfaction by means of a 10-item standardized questionnaire. A 36-item survey was administered before and after the course to assess participants' learning. Behavioural change was assessed by a 57-item safety attitude questionnaire measuring staff's change in attitude to safety over 1 year of programme implementation. RESULTS: Most participants valued the experience highly and 63-90% rated their level of satisfaction as being very high. Except for seven items, the 36-item survey testing participants' learning demonstrated a significant change (P<0.05) towards better knowledge of teamwork and shared decision making after the training programme. Over the year of observation, there was a positive change in the team and safety climate in the hospital [odds ratio (OR) 2.9, 95% confidence interval (CI) (1.3-6.3) to OR 4.7, 95% CI (1.2-17.2)]. **There was also improved stress recognition [OR 2.4, 95% CI (1.2-4.8) to OR 3.0, 95% CI (1.0-8.8)]. CONCLUSION: The implementation of a training programme based on CRM in a multidisciplinary obstetrical setting is well accepted and contributes to a significant improvement in interprofessional teamwork.