This work explores the development of aspects of discourse competence by French immersion students in Ontario, Canada. It represents a new front for second language acquisition and immersion research in that, firstly, it provides an in-depth analysis of the mastery by immersion students of several polysemous and poly-functional words (i.e., comme/like; donc/alors/(ça) fait que/so; bon; and là), words playing key roles in the expression of fundamental semantic notions (e.g., comparison, consequence, location) and discursive functions (e.g., emphasis, topic shifting, turn yielding). Secondly, it offers insight into the use of discourse markers by immersion students, an as yet under-researched area. Finally, it documents the influence on second language learners' discourse competence exerted by a range of independent factors, many of which have not before been applied to research on the development of this competence. Katherine Rehner completed her Ph.D. in Second Language Education at the Ontario Institute for Studies in Education at the University of Toronto and held a two-year federally-funded Canadian post-doctoral fellow-ship in the Department of French Studies and the Department of Languages, Literatures and Linguistics at York University. Her research to date has focused primarily on the development of sociolinguistic and discourse competencies by advanced second language learners of French.