Habitually speaking more than one language is progressively becoming the norm rather than the exception. Understanding exactly what the advantages are (and possible disadvantages, if any) of this new condition is essential in order to make informed and conscious choices on the management of multilingualism situations in our society, which affect various levels (from schools to services to institutions) and require adequate organizational models as well as new cultural paradigms. The still widespread myths that arise from the fear that the coexistence of multiple languages and cultures in the same territory could represent a source of confusion and hamper the development of the individual and the well-being of groups can now be debunked by scientific evidence. Research has in fact shown that multilingualism does not constitute a disadvantage for cognitive and linguistic development and that in fact it can bring advantages due to its capacity to stimulate executive functions, metacognition, Theory of Mind, up to and including the ability to empathize. However, specific preconditions are needed for these advantages to manifest, including sufficient quantity, quality and variety of exposure to the two or more languages and a positive attitude towards each of the languages spoken.