Scale Hierarchies in Particle Physics and Cosmology

We discuss possible connections between several scales in particle physics and cosmology, such the the electroweak, inflation, dark energy and Planck scales. We then describe the phenomenology of a model of supersymmetry breaking in the presence of a tiny (tunable) positive cosmological constant. The model is coupled to the MSSM, leading to calculable soft supersymmetry breaking masses and a distinct low energy phe- nomenology that allows to differentiate it from other models of supersymmetry breaking and mediation mechanisms