OBJECTIVES: To determine the effect of a consumer-directed information campaign to increase knowledge of folate for the prevention of neural tube defects among women of child-bearing age, and to measure women's recall of sources of information and knowledge about folate. DESIGN: A community randomized trial. SETTING: Three matched pairs of geographically distinct Local Government Areas in the state of Victoria, Australia. INTERVENTION: Printed information recommending folate intake to decrease the risk of neural tube defects was disseminated to women of child-bearing age in three of the Local Government Areas selected randomly. MAIN OUTCOME MEASURE: The proportion of women aware of the association between folate and spina bifida. RESULTS: Of 1197 women interviewed prior to the intervention, 12.4% (adjusted for the cluster and population sampling unit) were aware of folate and neural tube defects. After the intervention, there was not only a significant background increase of 3.4% (P=0.02) in folate awareness since the pre-intervention survey (n=603), but also a significant additional increase of 4.0% (P=0.04) owing to the intervention itself (n=603). Only 70% of women who were aware of folate knew the correct timing. CONCLUSIONS: The provision of printed educational material can increase folate awareness among women of child-bearing age. A comprehensive, long-term and ongoing health promotion campaign including such material, together with initiatives by relevant health service providers and the food industry, could best address the current low levels of folate awareness among women of child-bearing age.