The MERLIN project will aim to reduce the environmental impact of air transport using Additive Manufacturing (AM) techniques in the manufacture of civil aero engines. MERLIN will develop AM techniques, at the level 1 stage, to allow environmental benefits including near 100% material utilisation, no toxic chemical usage and no tooling costs, to impact the manufacture of future aero engine components (current buy to fly ratios result in massive amounts of waste). All of these factors will drastically reduce emissions across the life-cycle of the parts. There will also be added in-service benefits because of the design freedom in AM. Light-weighting and the performance improvement of parts will result in reduced fuel consumption and reduced emissions. MERLIN will seek to develop the state-of-the-art by producing higher performance additive manufactured parts in a more productive, consistent, measurable, environmentally friendly and cost effective way.