Neuroscientific research on bilingualism has traditionally focused on its functional implications. The brain is a continually changing organ (due to genetic as well as nongenetic causes), and language's pervasiveness in human behaviour allows to consider bilingualism as a highly demanding cognitive condition. During the last ten years, important developments of the neuroimaging techniques have boosted significant progresses in the knowledge about the neural correlates of language processing and representation. Many studies have shown that bilingualism might be involved in Grey Matter volume's changes in brain regions such as the inferior frontal Gyrus or the Posterior Supramarginal Gyrus, as well as in promoting a greater White Matter integrity in several brain structures. Furthermore, bilingualism has been recently linked to a delay of 4 to 5 years in the onset of dementia, so suggesting that it could be an effective strategy to enhance the Cognitive Reserve. Key words: bilingualism, Grey and White Matter, Cognitive Reserve