"United Marching - Marcher uni" is a specialized book that summarizes the results of a significant German-French research project on military cooperation between Germany and France. This project was conducted between 2005 and 2006 by the Social Science Institute of the Bundeswehr in Strausberg in collaboration with the Centre d'études en sciences sociales de la défense in Paris. The book offers a comprehensive analysis of the political and social aspects of this cooperation and highlights the challenges and opportunities arising from the collaboration of the two nations in the military field. It is aimed at professionals, students, and anyone interested in the topics of military, politics, and international relations. The content is presented in both German and French, which enhances accessibility for a wider audience.