Given the limitations of the SRS boost technique, the purpose of our investigation is to evaluate an alternative strategy for giving WBRT with highly focal boost to gross visible lesions in patients with brain metastasis. In this study, we plan to assess the tolerability of using volumetric modulated arc therapy (RapidArc) on patients with brain metastasis to simultaneously treat the entire brain with a concomitant focal boost to grossly identified lesions on MRI scan to try to improve local control and reduce neurocognitive toxicities.