"European military industry lobbying is playing an important role in the emergence of European defense. Within the framework of evolutionary institutionalism approaches, this article sets out to examine the role of the defense and security lobbying sector in its components; this is in order to analyze the influence of private sector powers on the causal cumulative process leading to the establishment and development of EU institutions. The analysis consists of two parts: in the first part, we will provide an institutionalist reading by setting the theoretical framework, then we will use Beckley’s study of sector lobbyists, bringing in new elements, to come to a description of lobbying members. In the second part, we will conduct a statistical empirical analysis which will aim to demonstrate the influence on lobbying of components of the public and private sectors."