In this talk, the methods used in multiscale modeling are reviewed. On the atomistic level, quantum mechanical calculations are needed in order to explain phenomena such as bond formation and breaking, diffusion barriers etc. Moving towards nanoscale, one can use the information obtained using the quantum mechanical calculations as input for classical molecular dynamics or Monte Carlo calculations. In these calculations, the presence of individual atoms is still taken into account, yet the detailed information on the electronic structure is missing. From this point on, several methods such
as phase field models and, eventually, finite element methods can be used to obtain the macroscopic properties.