Improvements in the understanding of human milk composition, in dietetic effects on physiological outcomes in infants, and in food technology have lead to modifications in infant formulas and other dietetic products for infants. In Europe, new ingredients may be added to infant formula and follow-on formulas if their suitability for particular use by infants from birth has been established by generally accepted scientific data. However, there is uncertainty as to the nature of the evaluation needed to evaluate whether modifications in dietetic products for infants can be regarded as suitable and safe. Moreover, there is no agreement on the nature of evidence required to justify the scientific validity of potential effects on infant health and well-being, which might provide the basis for the communication of such effects to health professionals and consumers. Therefore, a scientific workshop was held under the auspices of the Child Health Foundation, Munich, Germany, and the European Society for Paediatric Gastroenterology, Hepatology and Nutrition to discuss issues arising in this area among participants representing academia, infant food industry, consumer organisations, the European Commission, and food regulatory bodies of some European Union member states. This article summarises the outcomes of this workshop. The participants agreed on general concepts of evaluation of innovations and on establishing evidence for benefits, but felt that further discussion would be necessary on the principles and practicalities involved in setting up a central register of clinical trials and of a central repository of trial data.