Over the past four decades, measurements at the external beam lines of the CERN SPS have been at 
the center of worldwide attention. These experimental results have challenged QCD as our theory 
describing visible matter, thus serving as important input to develop improvements of the theory.

As of today, these beam lines remain unique and bear great potential for a significant future advancement 
of our understanding of hadronic matter.  Hence we propose to establish a world-unique QCD facility 
that will use the external SPS M2 beam line in conjunction with a universal spectrometer in the experimental 
hall EHN2. After a major upgrade in a second phase, it will be possible to produce unique beams with considerably 
enhanced fractions of kaons or anti-protons, thereby opening access to a wide range of new physics opportunities.

The Letter of Intent available on this site is summarizing most of the present ideas for possible 
future measurements to be performed at the CERN M2 beam line. It was prepared with the objective to 
serve as a basis for building a broad community dedicated to these new studies. During the forthcoming 
year the document is expected to evolve towards a full proposal for a new experimental facility. 
It is planned to be ready in time for the 2019/2020 Update of the European Strategy for Particle Physics.