We briefly review the work carried out in project A1 of the SFB 676. This includes in particular string compactifications to vacua containing the Standard Model. We compare heterotic compactifications with F-theory, and we mention a number of technical developments. Motivated by string compactifications, several aspects of six-dimensional field theories are described, which shed some light on supersymmetry breaking, moduli stabilization and the little hierarchy problem. We highlight some virtues of flux compactifications and conclude with a brief discussion of LHC phenomenology.