Ellen Bialystok is a Distinguished Research Professor of Psychology and Walter Gordon Research Chair of Lifespan Cognitive Development at York University. She is an Officer of the Order of Canada and a Fellow of the Royal Society of Canada. Her research uses behavioral and neuroimaging methods to examine the effect of bilingualism on cognitive processes across the lifespan. Her discoveries include the identification of differences in the development of cognitive and language abilities for bilingual children, the use of different brain networks by monolingual and bilingual young adults performing cognitive tasks, and the postponement of symptoms of dementia in bilingual older adults. Recent studies have investigated the effects of bilingual education on children’s development and the cognitive and brain consequences of bilingualism in older adults. Her current research is examining how lifelong bilingualism may be protective for cognitive decline in older age and contribute to cognitive reserve.