The Southampton Initiative for Health is a training intervention with Sure Start Children's Centre staff designed to improve the diets and physical activity levels of women of childbearing age. Training aims to help staff to support women in making changes to their lifestyles by improving three skills: reflection on current practice; asking 'open discovery' questions; and goal-setting. The impact of the training on staff practice is being assessed. A before and after non-randomized controlled trial is being used to evaluate the effectiveness and cost-effectiveness of the intervention in improving women's diets and increasing their physical activity levels.