The context
This year will see the launch of the much awaited Large Hadron Collider, LHC. The main raison d'être of this major international project has been the elucidation of the mechanism of symmetry breaking and the concomitant problem of the mass of all elementary particles through the search of the elusive Higgs particle. The Higgs is the missing link in the much successful Standard Model, SM, description of high energy physics. In fact, when it comes to the sector of symmetry breaking, there are numerous theoretical arguments that hint to New Physics so that we expect a wealth of new data at the LHC. Apart from various theoretical arguments, most recent observations like the celebrated WMAP (Wilkinson Microwave Anisotropy Probe) have confirmed that ordinary matter accounts for a minute portion of what constitutes the Universe at large. There is an overwhelming dominance of Dark Energy and Dark Matter, DM. This, in itself, is New Physics. Add to this that the majority of models for the New Physics whose primary aim is a better description of the Higgs sector of the SM provide as a bonus a  candidate for DM, it is fair to say that we are witnessing the emergence of a strong cross breeding between high energy collider physics on the one hand and cosmology and astrophysics on the other to unravel the mystery of DM. It is also important to stress that at about the same time as the LHC will be gathering data, other significant experiments (PLANCK, GLAST, AMS, HESS, CDMS, Edelweiss,...) will have provided or will be providing unprecedented information on DM and hence on the New Physics.  It is therefore of utmost importance to get ready for the analyses and combination of the wealth of  data from these upcoming non-collider observations with those at the LHC. This will also pave the way to search strategies for a future international e+e- Linear Collider, ILC.  This important programme is only possible if a cross-border particle-astroparticle collaboration is set up, having at its disposal common or complementary tools to conduct global combined analyses. Moreover it is crucial to associate theorists and experimentalists from these two communities for such a project.