Development of new materials is a challenging task which involves not only selecting the final properties but also the whole processing route. Experimental verification is very important but very expensive and to limit the cost and time for the development one regularly uses computer simulations for many steps. For equilibrium calculations the Calphad method provides facilities to calculate phase diagrams but also many other kinds of diagrams providing phase amounts, chemical potentials and heat capacities at varying temperature and compositions. But a very important feature of the assessed Calphad thermodynamic databases is that they provide information about phase amounts, chemical potentials etc also for the metastable states during phase transformations. Combined with Phase Field Methods or other kinetic models the use of validated and assessed thermodynamic databases is essential.