BACKGROUND The US National Cancer Institute alert in February, 1999, stated that concomitant chemotherapy and radiotherapy should be considered for all patients with cervical cancer. Our aim was to review the effects of chemoradiotherapy on overall and progression-free survival, local and distant control, and acute and late toxicity in patients with cervical cancer. METHODS With the methodology of the Cochrane Collaboration, we did a systematic review of all known randomised controlled trials done between 1981 and 2000 (17 published, two unpublished) of chemoradiation for cervical cancer. RESULTS The trials included 4580 randomised patients, and 2865-3611 patients (62-78%) were available for analysis. Cisplatin was the most common agent used. The findings suggest that chemoradiation improves overall survival (hazard ratio 0.71, p<0.0001), whether platinum was used (0.70, p<0.0001) or not (0.81, p=0.20). A greater beneficial effect was seen in trials that included a high proportion of stage I and II patients (p=0.009). An improvement in progression-free survival was also seen with chemoradiation (0.61, p<0.0001). Thus, the absolute benefit in progression-free and overall survival was 16% (95% CI 13-19) and 12% (8-16), respectively. A significant benefit of chemoradiation on both local (odds ratio 0.61, p<0.0001) and distant recurrence (0.57, p<0.0001) was also recorded. Grade 3 or 4 haematological (odds ratio 1.49-8.60) and gastrointestinal (2.22) toxicities were significantly greater in the concomitant chemoradiation group than the control group. There was insufficient data to establish whether late toxicity was increased in the concomitant chemoradiation group. CONCLUSIONS Concomitant chemotherapy and radiotherapy improves overall and progression-free survival and reduces local and distant recurrence in selected patients with cervical cancer, which may give a cytotoxic and sensitisation effect.