The aim of this study was to explore inhibiting factors in the prevention of overweight in infants younger than one year, among practitioners working for municipal child healthcare organisations in the Netherlands. Twelve in-depth interviews with child healthcare physicians and nurses were conducted. All interviews were tape-recorded, after which the transcripts were thematically analysed. Two investigators separately coded two transcripts to verify coding and a final code book was developed. Finally, general conclusions were drawn from the interviews. The findings indicated that child healthcare practitioners are insufficiently aware that a child's first year is an important period to prevent overweight, and that they find it difficult to discuss the topic with parents. Additionally, the findings suggest that the current local overweight prevention protocols in the Netherlands are not well implemented. This study indicates opportunities to improve the performance of child healthcare practitioners with respect to the early identification of infants at risk for overweight, as well as the communication of this risk to parents and the implementation of overweight-prevention protocols. (Contains 1 figure and 2 tables.)