Background Caesarean section rates are steadily increasing globally. The factors contributing to these observed increases are complex. Non-clinical interventions, those applied independent of patient care in a clinical encounter, may have a role in reducing unnecessary caesarean sections. Objectives To evaluate the effectiveness and safety of non-clinical interventions for reducing unnecessary caesarean sections. Search methods We searched the following electronic databases: the Cochrane Effective Practice and Organisation of Care (EPOC) Group Specialised Register (29 March 2010), the Cochrane Pregnancy and Childbirth Group Specialised Register (29 March 2010), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2010, Issue 2); MEDLINE (1950 to March 2010); EMBASE (1947 to March 2010) and CINAHL (1982 to March 2010). Selection criteria We included randomised controlled trials (RCTs), quasi-experimental studies, controlled clinical trials (CCTs), controlled before and after studies (CBAs) with at least two intervention and control sites, and interrupted time series analyses (ITS) where the intervention time was clearly defined and there were at least three data points before and three after the intervention. Studies evaluated non-clinical interventions to reduce unnecessary caesarean section rates. Participants included pregnant women and their families, healthcare providers who work with expectant mothers, communities and advocacy groups. Data collection and analysis Three review authors independently assessed the quality and abstracted data of all eligible studies using a standardised data extraction form, modified from the Cochrane EPOC checklists. We contacted study authors for additional information. Main results We included 16 studies in this review. Six studies specifically targeted pregnant women. Two RCTs were shown to be effective in reducing caesarean section rates: a nurse-led relaxation training programme for women with a fear or anxiety of childbirth and birth preparation sessions. However, both RCTs were small in size and targeted younger mothers with their first pregnancies. There is insufficient evidence that prenatal education and support programmes, computer patient decision-aids, decision-aid booklets and intensive group therapy are effective. Ten studies targeted health professionals. Three of these studies were effective in reducing caesarean section rates. A cluster-RCT of guideline implementation with mandatory second opinion resulted in a small, statistically significant reduction in total caesarean section rates (adjusted risk difference (RD) -1.9; 95% confidence interval (CI) -3.8 to -0.1); this reduction was predominately in intrapartum sections. An ITS study of mandatory second opinion and peer review feedback at department meetings found statistically significant results at 48 months for reducing repeat caesarean section rates (change in level was -6.4%; 95% CI -9.7% to -3.1% and change in slope -1.14%; 95% CI -1.9% to -0.3%) but not for total caesarean section rates. A cluster-RCT of guideline implementation with support from local opinion leaders increased the proportion of women with a previous caesarean section being offered a trial of labour (absolute difference 16.8%) and the number who had a vaginal birth (VBAC rates) (absolute difference 13.5%). The P values are, however, not reported due to unit of analysis errors. There was insufficient evidence that audit and feedback, training of public health nurses, insurance reform, external peer review and legislative changes are effective. Authors' conclusions Implementation of guidelines with mandatory second opinion can lead to a small reduction in caesarean section rates, predominately in intrapartum sections. Peer review, including pre-caesarean consultation, mandatory secondary opinion and postcaesarean surveillance can lead to a reduction in repeat caesarean section rates. Guidelines disseminated with endorsement and support from local opinion leaders may increase the proportion of women with previous caesarean sections being offered a trial of labour in certain settings. Nurse-led relaxation classes and birth preparation classes may reduce caesarean section rates in low-risk pregnancies.