In this paper, I examine the contextual factors that impact the development ofknowledge base of teachers of English as a second language (ESL) and French as asecond language (FSL) for teaching in Kindergarten through Grade 12 programs inOntario. Using a sociocultural orientation to second language teacher education andprominent knowledge base frameworks from the field, I discuss how a variety oflocal contextual factors impact the development of teacher candidates’ (TC)knowledge base in pre-service teacher education programs in Canada. Individualfactors include: the linguistic and cultural backgrounds of candidates’ in ESL andFSL programs, the TCs’ language proficiency in the target language, their personalexperiences and understanding of language development, and their familiarity withreal life experiences of ESL and FSL students. Beyond their own experiences,integral to TCs knowledge base are the range of student populations they couldserve and the variety of language teaching contexts they can encounter in theOntario context. I discuss the implications of such nuances for policy and practicein language teacher education programs across Canada.