Miekisz J. Stable Quasicrystalline Ground States (31K, LATEX) ABSTRACT. We give a strong evidence that noncrystalline materials such as quasicrystals or incommensurate solids are not exceptions but rather are generic in some regions of a phase space. We show this by constructing classical lattice gas models with translation-invariant finite range interactions and with unique quasiperiodic ground states which are stable against small perturbations of finite range potentials.