Study of brain tumors (BT) has revealed the importance of cognitive and behavioral assessment to clinical care and prognosis. This paper overviews recent literature, focusing on the main points of interest and current methods, providing recommendations for advancing research. Histological aspects, disease progression, treatment-related neurotoxicity, and co-morbidities determine the cognitive patterns of BT. Mental slowing with prominent executive and memory compromise usually mark the advanced phases of disease, whereas normal cognitive performance or subtle behavioral symptoms characterize the early disease course, irrespective of tumor location. Neurocognitive assessment may indicate brain damage in otherwise neurologically normal patients, explain pathological behavior, and provide reliable measures of outcome, contributing to improving the management of patients. Scarce attention has been devoted to social cognitive deficits which are expected to impair autonomy and relationships. Interest in non-pharmacological treatment of cognitive impairment is a growing area although methodological difficulties persist. Homogeneous patient populations, longitudinal study designs including baseline evaluations, and measurement of the lowest and highest levels of cognitive performance seem indispensable to advancing the study of the cognitive and behavioral changes provoked by BT. Future investigations are also expected to clarify the clinical significance of such changes, their effect on quality of life, and the efficacy of specific rehabilitation treatments.