We review recent work on property decomposition techniques using quantum emical methods and discuss some topical applications in terms of antum mechanics-molecular mechanics calculations and the constructing properties of large molecules and clusters. Starting out from the -called LoProp decomposition scheme [Gagliardi et al., J. Chem. Phys., 04, 121, 4994] for extracting atomic and inter-atomic contributions to lecular properties we show how this method can be generalized to calized frequency-dependent polarizabilities, to localized perpolarizabilities and to localized dispersion coefficients. Some plications of the generalized decomposition technique are reviewed - lculations of frequency-dependent polarizabilities, Rayleigh attering of large clusters, and calculations of hyperpolarizabilities proteins.