Abstract The Community‐Based Nutrition Component of the Bangladesh Integrated Nutrition Project sought to improve nutritional status through nutritional counselling and supplementary feeding for malnourished children and pregnant women. This paper presents a theory‐based impact evaluation of this programme. Both counselling and feeding suffered from problems of inappropriate targeting strategies and a failure to reach intended groups. While counselling has changed women's knowledge it has had less of an impact on behaviour. There is a knowledge‐practice gap, which is explained by resource constraints faced by women, including lack of time, which prevent them from putting the advice into practice. The impact of the project on anthropometric outcomes of infants, children and mothers has not been large. Copyright © 2006 John Wiley & Sons, Ltd.