While European countries tend to increase the importance given to their national environmental health action plan (NEHAP), Switzerland stopped implementing its NEHAP in 2007. This study investigates the reasons for this surprising decision. The results provide an explanation of a relatively unique case and should inform any person interested in understanding common obstacles in the making and implementation of coordinated environmental health policies and programs. Data used in this study have been obtained from interviews conducted among experts of the Swiss environmental health policies and from survey results provided by the WHO Regional Office for Europe. Findings show that financial constraints were only partly responsible for the abandonment of the NEHAP and that many of the shortcomings observed arose from the creation and the functioning of the Environmental and Health Section at the Federal Office of Public Health, which was devoted to the NEHAP. Lack of scientific knowledge and capacity to build intersectoral collaboration, compounded by a limited conception of environmental health, resulted in a lack of political awareness of environmental health issues. In consequence, the study highlights the necessity of a true interdisciplinary and intersectoral approach for environmental health policies. Policy makers should also be concerned with the creation of relevant systems of indicators, since they appear to be fundamental to the success of environmental health policies.