METRO-HAUL is a project proposal addressing the Horizon 2020 ICT-07 5G PPP call; it is an RIA, focusing on strand 2 (high capacity elastic – optical networks) and strand 3 (software networks). The central topic is cost-efficient optical metro networks for 5G backhaul. The aim of this project is to design and build a smart, but cost-effective, optical metro infrastructure able to support traffic originating from heterogeneous 5G access networks, addressing the anticipated capacity increase and its specific characteristics such as mobility, low latency, and high bandwidth. This infrastructure will be able to also support a wide variety of 5G applications with special emphasis on services from various industries vertical to the ICT. This will be achieved by architecting new access-facing and core-facing nodes, complete with storage and compute facilities, interconnected by novel, spectrally efficient, and adaptive optical transmission networks. Advanced concepts, such as hardware disaggregation and virtualisation, will assist in hitting challenging cost targets whilst enabling automation and programmability – all supported by a purpose-designed SDN-based control plane which will interface with client applications, intelligently catering for the wide range of 5G KPIs. METRO-HAUL will coordinate the disparate elements of transmission, switching, networking, compute, and storage, orchestrating dynamic solutions for multiple 5G applications. METRO-HAUL will carry out Proof of Concept demonstrations of its networking solution involving the interconnection of metro node prototypes, the use of the project's transmission technologies, and the associated control plane and orchestration software. The final project demonstrations will also involve the demonstration of actual 5G and vertical services across the METRO-HAUL test-bed. Additionally, the project will actively participate in the relevant standardization bodies, promoting METRO-HAUL solutions to the wider community.