"String Theory is the leading candidate for a theory of quantum gravity including Particle Physics. In the last ten years important progress has been made in the construction of string theory solutions resembling the Standard Model (SM) of Particle Physics. String compac- tifications giving rise to the gauge group of the SM and three generations of quarks and leptons have been constructed. It has also recently been found that quantized fluxes of the anti-symmetric fields present in the theory provide for a solution for the long standing problem of moduli stabilization in String Theory. On the other hand a new era for Particle Physics has begun with the starting into operation of the LHC accelerator in 2010. The new data is expected to reveal the origin of the masses of all particles and what is the physics underlying it. New forces or symmetries like supersymmetry, extra dimensions etc. could be found. Whatever is found it will provide stringent tests of models for physics beyond the SM and also string theory compactifications. The purpose of this project is to make progress in the construction of string semi-realistic solutions and try to obtain information from the LHC data in order to constraint the underlying theory. In order to do that a general study of different classes of string compactifications will be made. If e.g. supersymmetry is found at LHC, we will be able to compare the structure of soft SUSY-breaking soft terms in large classes of string models with experimental data, giving important information about the underlying string theory. One of the objectives of the project is to answer the question: What is LHC telling us about string Theory?"