Using moral and empirical analysis, we analyzed and discussed the role of public health in prevention of war as well as its function during and after the war. The idea is to develop a theory and new strategy in the spirit of public health to improve practices in preserving and strengthening peace, to be prepared for the future. The experiences from the last four wars in South Eastern Europe were ethical challenges to public health. We identified and described four models of public health practice in the past wars and conflicts. Based on the recent wars, the two new models, Professional Model and Peace Model, were developed and suggested as a new public health strategy in prevention and alleviation of the health burden of war.