I introduce a new tool, SModelS for decomposing generic SUSY spectra into SMS topologies and testing them against the existing Simplified Model Spectra (SMS) limits from the LHC. While the current implementation focuses on supersymmetry, the tool is in principle applicable to any beyond the Standard Model theory respecting a Z2 symmetry. I will explain the working principle of SModelS, as well as its validation and limitations. I will exemplify the applicability of SMS results to SUSY parameter space and discuss how we can learn more about improving the representation of experimental results in an efficient fashion. (arXiv:1312.4175) As a physics-case example, I will then present the application of SModelS in a study of light neutralino dark matter in the MSSM (arXiv:1308.3735). Here I will discuss the viability of light neutralino DM with mass below 35 GeV consistent with LHC bounds. Higgs search results as well as direct and indirect DM detection constraints are taken into account.