OBJECTIVE: To assess the evidence for the efficacy of local treatments for cutaneous warts. METHODS: Systematic review of randomised controlled trials. MAIN OUTCOMES MEASURES: Total clearance of warts and adverse effects such as irritation, pain, and blistering. STUDY SELECTION: Randomised controlled trials of any local treatment for uncomplicated cutaneous warts. All published and unpublished material was considered, with no restriction on date or language. RESULTS: 50 included trials provided generally weak evidence because of poor methods and reporting. The best evidence was for topical treatments containing salicylic acid. Data pooled from six placebo controlled trials showed a cure rate of 75% (144 of 191) in cases compared with 48% (89 of 185) in controls (odds ratio 3.91, 95% confidence interval 2.40 to 6.36). Some evidence for the efficacy of contact immunotherapy was provided by two small trials comparing dinitrochlorobenzene with placebo. Evidence for the efficacy of cryotherapy was limited. No consistent evidence was found for the efficacy of intralesional bleomycin, and only limited evidence was found for the efficacy of topical fluorouracil, intralesional interferons, photodynamic therapy, and pulsed dye laser. CONCLUSIONS: Reviewed trials of local treatments for cutaneous warts were highly variable in methods and quality, and there was a paucity of evidence from randomised, placebo controlled trials on which to base the rational use of the treatments. There is good evidence that topical treatments containing salicylic acid have a therapeutic effect and some evidence for the efficacy of dinitrochlorobenzene. Less evidence was found for the efficacy of all the other treatments reviewed, including cryotherapy.