Recently, the focus of Irish transport policy has shifted significantly towards sustainable infrastructure development. Transport Infrastructure Ireland (TII) published National Roads 2040 (NR2040), which responds to policy shift placing greater emphasis on multi-modal solutions, decarbonisation, and sustainability. This research paper explores the underlying analysis of NR2040, including; (1) how it aligns with Government policies and plans, (2) underlying analysis of future scenarios; functional corridor assessment of national secondary roads; and estimation of road transport emissions, and (3) the NR2040 implementation and investment approach. In respect to methods, research topics 1 and 3 are primarily policy reviews, while the work involved with research topic 2 required extensive analysis and research tools including TII’s VISUM-based National Transport Model (NTpM) and the Irish Road Emissions Model (REM). The development of a comprehensive road transport strategy (NR2040) is a critical part of the national policy effort to reduce negative externalities associated with motorised vehicles and contribute towards the achievement of climate action targets. Thus, NR2040 provides a valuable case study for policy makers and researchers, showcasing a national shift away from the traditional ‘predict and provide’ model of transport planning in a modern European country with high car dependency and a large rural population.