In the recent swell of research on bilingualism and its consequences for the mind and the brain, there has been a warning that we need to remember that not all bilinguals are the same (e.g., Green & Abutalebi, 2013; Kroll & Bialystok, 2013; Luk & Bialystok, 2013). There are bilinguals who acquired two languages in early childhood and have used them continuously throughout their lives, bilinguals who acquired one language early and then switched to another language when they entered school or emigrated from one country to another, and others who only acquired a second language (L2) as an adult. Among these forms of bilingualism there are differences in both the context and amount of time spent in each language and differences in the status of the languages themselves. The L2 may be a majority language, spoken by almost everyone in the environment, or a minority language, spoken only by a few. The native or first language (L1) may also be the dominant language or may have been overtaken by the influence of the L2 given the circumstances imposed by the environment. Likewise, the L1 and L2 may vary in how similar they are structurally, whether they share the same written script, or whether one language is spoken and the other signed.