glioma (brain tumor) invasion depends on its microenvironment. we will present two models in this talk. we first analyze the migration patterns of glioma cells from the main tumor, and show that the various patterns observed in experiments can be obtained by a model's simulations, by choosing appropriate values for some of the parameters (chemotaxis, haptotaxis, and adhesion) of the pde model. for the second part of talk, we introduce a multiscale model in order to get more detailed informations on cell migration. the results of such an approach are compared to the experimental data as well. *this is joint work with avner friedman (mbi), sean lawler, michal o. nowicki, e. antonio chiocca (oncological neurosurgery), jed johnson, john lannutti (lannutti lab) at the ohio state university, and hans othmer (university of minnesota).