Zeolites form an important class of inorganic materials with an enormous industrial interest which derives from their molecular sieving, ion-exchange and catalytic properties. The research in this field now takes advantage on advanced modeling programs which allow us to examine in details the structure of these complex materials and their interactions with adsorbed species both under static or dynamic conditions. The information obtained is often fundamental for better understanding of the mechanism of formation of these materials and their shape selective properties. In this paper, selected applications of modeling in zeolite science are presented and discussed.