COSAC has played an active role in fostering and developing interparliamentary cooperation since it has proven to be an effective model that has helped shape a supranational layer of influence for NPs. The central question addressed here is to assess whether COSAC is currently structured to allow NPs to obtain more information and access to the policy and decision-making circuits at EU level and, therefore, if NPs are benefiting from COSAC or are they, on the contrary, lagging behind and lost amidst so many interparliamentary meetings? It is argued that COSAC occupies a key role in the multipolarised system of interparliamentary cooperation, because it is the conference with the “global picture” and therefore in a unique position to bring coherence to the overall system. This paper therefore aims at putting forward some ideas and approaches regarding the role of COSAC in the effectiveness of interparliamentary cooperation, covering not only its present proceedings and output, but also some thoughts for further reflection on the future strengthening of COSAC.