This paper presents an overview of the first variable examined in the Heritage Language Variation and Change in Toronto project (Nagy 2009), which strives to apply consistent methodology across multiple language-contact contexts and variables to advance our understanding of contact-induced change. It is principally comprised of sociolinguistic interviews conducted in Toronto with 40 speakers from each of six heritage languages (Cantonese, Faetar, Italian, Korean, Russian and Ukrainian). Participants are also asked about their ethnic identification, language use, and linguistic attitudes (Keefe & Padilla 1987, Hoffman & Walker 2010). Responses are translated into index scores to quantify each speakers' orientation toward their heritage language/culture and their English/"Canadian" culture. Here we examine the effects of a constellation of factors (linguistic, typological, demographic, social) on a single linguistic variable: (pro-drop). Our Cantonese, Italian and Russian data, ~6,000 tokens, is contrasted with a sample from the Toronto English Archive (Tagliamonte & Denis 2010). For comparability with previous studies of pro-drop, we examine the effects of continuity of reference (Cameron 1995), contextual/formal ambiguity of the subject's referent (Paredes Silva 1993), clause type (Harvie 1998), priming by the preceding subject (Torres Cacoullos & Travis 2010), person and number of the subject, and tense of the following verb. Pro-drop rates and constraint hierarchies in each HL show no relationship to any indices of generation since immigration, ethnic identity or language use, suggesting that this variable is not used to construct ethnic identity and is not undergoing change as the heritage varieties of each language develop in Toronto.