Objective The ToyBox proposal addresses KBBE-2009-2-1-03 - Behavioural models for prevention of obesity, with a particular focus on children. It will primary aim to influence children’s behaviours and prevent obesity in early childhood. Strategy The proposal will identify key behaviours related to early childhood obesity and their determinants and evaluate behavioural models and educational strategies. Based on the obtained insights at a local level, a multidisciplinary team will develop and implement a school based family involved intervention programme that could be applied on a European scale. Process, impact, outcome and cost-effectiveness evaluation will be conducted to support decision making for European Public Health Policy. Methods The combined use of Precede-Proceed Model and Intervention Mapping will provide the framework for the development, implementation and evaluation of the ToyBox intervention. To achieve this, the project will be subdivided into 10 WPs. This carefully planned stepwise approach will include systematic reviews, secondary analyses of existing data sets, focus group research and school policies overview. Consortium The ToyBox project consortium spans the necessary multidisciplinary variety of experts such as public health experts, epidemiologists, nutritionists, physical activity experts, pedagogists, psychologists, behavioural scientists, nutritionists, paediatricians, early childhood psychologists, health economists, totalling 15 partners, from 10 countries. The consortium, consists of 11 universities, 1 research institute, 2 advocacy groups and an SME representing all regions of Europe. The consortium has ample experience in conducting and coordinating multi-centre international research as well as undertaking dissemination activities to all relevant stakeholders.