Effective advocacy is essential for meeting global targets for stunting reduction and other nutritional problems. The purpose of this paper is to strengthen the understanding and the practice of advocacy in relation to nutrition, in support of the current global and national efforts to reduce stunting and other nutrition problems. While there is a substantial grey and published literature with useful frameworks, principles and recommended practices for advocacy, there has been relatively little systematic study in relation to stunting, or chronic undernutrition more broadly. The strategies and tactics, achievements and lessons learnt are described for three case studies: Uganda, Vietnam and Bangladesh. These cases, and experience from elsewhere, demonstrate that concerted, well-planned and well-implemented advocacy can bring significant achievements, even in short period of time. In light of the global and national attention being given to stunting reduction through the SUN (Scaling Up Nutrition) movement and other initiatives, there is now a need for much stronger investments in strategic and operational capacities for advocacy, including the human, organisational and financial resources for the advocacy and strategic communication themselves, as well as for monitoring and evaluation, supportive research and institutional capacity-building.