ABSTRACTThis review is dedicated to the application of the self-consistent-charge density-functional-based tight-binding (SCC-DFTB) approach to describe the structures, energetics, thermodynamic and spectral properties of water clusters, in the context of both fundamental and applied studies. We first present modifications implemented in the parametrisation of the potential that is mandatory to describe molecular aggregates as well as methods for global optimisation and determination of macroscopic properties. Then a number of applications of atmospherical and astrophysical interest, involving collaborations between theoreticians and experimentalists, are discussed to exemplify past and present contributions of SCC-DFTB to those two domains. Most applications presented in this review take advantage of the computational efficiency of SCC-DFTB to conduct extensive molecular dynamics simulations to obtain spectral and thermodynamic properties of water clusters. We also show some new results related to ongoing studies on both water clusters with impurities and liquid water.