The Action has initiated the process to identify key actors in family support in each country, building up National Working Groups that can support the achievement of the Action objectives and can benefit from its advances. These groups play an input and an advocacy role at national level on Action-related tasks, serve to build network capacity and operate to further develop family support at national level. National representatives currently members of the Action have been pointed out to fill in a template with information about key family support actors at national level. The template consisted of 11 items, 6 of which concerning information on the national partners (surname, contact information, name of the organization they belong to, their role in said organization, and whether they were already members of the action) and 5 relevant to the organization the partners belonged to (brief description of the organization, type of organization, scope, sector and other relevant information). From the 35 countries that are currently members of the Action, 17 have already mapped their National Working Groups: Albania, Bosnia, Bulgaria, Croatia, Estonia, Italy, Hungary, Latvia, Lithuania, Macedonia, Moldova, Poland, Portugal, Serbia, Slovenia, Spain and the UK. The national working groups were divided according to the size of their network in three categories: with 9 small-sized (networks less than 10 members), 4 medium-sized (between 10 and 30 members) and 4 large-sized networks (more than 30 members). Total percentages and the percentages dependent on the size of the network were calculated. Results showed that there are 281 NWGs partners that did not belong to the Action, most of them representing national organizations, with international, regional and local organizations less represented, except on Spain and Macedonia, where regional and local partners were widely included. In addition, all countries have included national partners from different types of organizations, the most represented types of organizations are state/public, NGOs and academic and research, whereas the least represented are front-line practitioners, except in Hungary, where half of their national partners were front-line practitioners. Small-sized networks have focused on partners that represent organizations from both state/government and NGOs, while medium sized networks included more state/government and academic and research, large sized networks had a more balanced representation of all types of organizations. Finally, there are many sectors represented in the different NWGs, being the most common ones, child protection and welfare, education, research and early years care and education. Although, we do not have full and representative account of the operation of family support organizations, these data provide information about the diversity in the approach towards the task of building national networks, as well as its relevance for the engagement and increasing of the reach of the network. The diversity of types of organizations and sectors involved, help guarantee the bottom-up structure and double layer of EurofamNet.