The European Network for Rural Development (ENRD) and National Rural Networks (NRNs) are part of the second pillar of the Common Agricultural Policy since the 2007-2013 programming period. The ENRD brings together stakeholders from across the EU and facilitates the exchange between national networks, organisations, and administrations with an interest in EU rural development. The NRNs are mainly established at national level in each Member State and bring together stakeholders involved in Rural Development. The study highlights the causal mechanisms of networks and governance structures that contribute to the implementation of the EU Rural Development policy. The various activities carried out by the ENRD are deemed effective to involve NRNs in networking at EU level although participation is heterogeneous across Member States, notably due to language barriers. Capacity building and knowledge transfers enabled by ENRD activities improved the implementation of Rural Development Programmes (RDPs) and policy. The Evaluation Helpdesk’s substantive support to the evaluation of RDPs improved the quality of evaluations but with little use in terms of policy learning. The organisational structure of NRN’s Network Support Units influence their efficiency; a hybrid system where policy coherence is provided by the Managing Authority and outsourcing parts of the activities is among the efficient models. The ENRD activities are coherent and complementary with the activities of the NRNs. The ENRD and the EIP-AGRI operated alongside each other with limited complementarity and synergies. Substantial EU added value is provided through stakeholders involvement and the provision of capacity building, in turn contributing to better RDP delivery and generating social capital. Finally, the network’s activities were relevant to strategic needs and rural challenges.