It gives me great pleasure to introduce this Special Issue of Applied Psycholinguistics. One might say that it was very Canadian in its conception. The period between Christmas and New Years 2004 was particularly cold in Montreal and Toronto. It was during this very cold snap that Ellen Bialystok, Fred Genesee, and I decided to apply to the Social Sciences and Humanities Research Council of Canada for special funding to host a conference on bilingualism. To make matters worse, one of our universities only heated its offices to the bare minimum during the holidays, and Ellen Bialystok's furnace broke down. With cold fingers, time running short, and the holiday period in full swing, we nevertheless managed to contact a dozen leading researchers from several countries who consented to become main speakers at the conference, Language Acquisition and Bilingualism: Consequences for a Multilingual Society, held in Toronto in May 2006 (a much warmer event). These researchers were joined by more than 300 people from 34 countries around the world, 119 of whom presented posters of their research (chosen from 250 submissions). The eager response of our research and practitioner communities for the conference and the compelling importance of the policy, educational, and program implications of bilingualism in a global context convinced me, as Editor of the Journal, that we should share the interest of the conference with you, the readers of Applied Psycholinguistics. This Special Issue contains articles by a number of the conference's speakers, and it was jointly edited by Ellen Bialystok and me with the help of Fred Genesee.