Abstract : Globalization is an anthropological and essential transformation at both levels, microeconomic and macroeconomic (countries, organizations, and people). In this paper, we present a traditional research based on an in-depth applied experiment of SEAM intervention in a French family business. Our research hypothesis is that during the internationalization process, management consulting practices, such as socio-economic intervention-research, help family businesses manage their internationalization process at different stages: decision-making, strategic implementation and performance piloting through measuring hidden costs and performance. We present our research results about the internationalization process of our family company case and show how, as researcher-consultants, we contribute to make this process more successful.