Multilingualism is achieved through different paths, at different ages, and for different purposes. But languages matter, and the experiences and abilities we acquire with languages impact our cognitive, social, and emotional lives. Moreover, we are now in a position in which we can control our language learning experiences and opportunities to a far greater degree than previously possible, so it is important to pause and examine what we know about multilingualism, foreign language learning, and their effects on individuals and families. The global and historical prevalence of multilingualism should be reassuring to those who struggle with the decisions around language use in their families and communities but we still want to make the best decision possible. The purpose of this book is to examine what is known about these issues in order to understand the impact of multilingualism on children

Ellen Bialystok is a Distinguished Research Professor of Psychology and Associate Scientist at the Rotman Research Institute of the Baycrest Centre for Geriatric Care. 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 essential cognitive and language abilities for bilingual children, the use of different brain networks by monolingual and bilingual young adults performing simple conflict tasks, and the postponement of symptoms of dementia in bilingual older adults.