This article presents a process-oriented mixed-method study, focusing on the emergence of second language (L2) critical thinking (CT) skills in the collaborative discourse produced by a focal group of five college-level students of French working in a virtual language learning environment (the VLLE Cinet Second Life). Levels of CT ability were elicited through episodes of L2 negotiation and co-construction of meaning. The study also examines the perception by students of the impact of the VLLE on the emergence of their L2 CT skills. Motivated by the need advocated in recent CALL research for a shift in paradigm and in method to alleviate the limitations inherent to quantitative studies, the study was situated at the juncture of sociocultural theory and ecological perspective, and this article focuses on the theoretical rationale behind the selection of a mixed-method methodology.