This session is aimed towards an audience primarily of radiation oncologists with the goals of updating them on the use of modern imaging techniques for diagnosis, treatment planning, and response assessment for brain tumors. The lectures will primarily cover these issues for glioblastoma, as imaging and response assessment has evolved rapidly for this tumor over the past several years. The lecture will begin with basic brain tumor imaging (T1, T2, SPGR, FLAIR sequences), then cover more novel imaging modalities (perfusion, DWI). The second half of the lecture will focus on the integration of emerging biologic imaging into modern treatment planning techniques. At the conclusion of this activity, the learner will be able to do the following: 1. Recognize response criteria for gliomas. 2. Describe the value of different imaging modalities in the brain and how they may be utilized for various brain tumors both in the pre-treatment and post-treatment setting. 3. Describe modern treatment planning methods for brain tumors.