For the majority of European adults, who neither smoke nor drink excessively, the most significant controllable risk factors affecting their long-term health are what they eat, and how physically active they are. Scientists are supposed to clarify to policy makers and health professionals the usefulness of their health messages. However, to be able to do that, a more detailed understanding is needed of the basic mechanisms behind the effects on health of diet and physical activity and, especially, the two in combination. Further, better methods for assessment of nutrition and physical activity in the population have to be developed, and more and better baseline data have to be collected. Increased and more efficient interventions are then needed. People trained and competent in the new discipline of Public Health Nutrition are required. Through the stimulating support that the European Commission, as well as other national and international partners, are presently giving to the development of Public Health Nutrition across Europe, we can hope for an increased mobility, networking and understanding between European nutrition and physical activity professionals. This will most likely result in greater and better policy making, strategy development, implementation and evaluation. We now have a great possibility to develop the integrated field of preventive nutrition and health enhancing physical activity.