This study illustrates different practices of knowledge co-construction by exploring argumentation processes from its (1) cognitive, (2) affective, and (3) moral dimensions (respect), and by clarifying the meaning of cooperation and collaboration, terms that are commonly used as synonyms. The authors adopted a critical constructivist approach consistent with the cognitive and moral works of Habermas (1987) and Piaget (1977, 1932/2000), and refined a method of online argumentation analysis (Campos, 2004) to better understand knowledge co-construction in the context of electronic conferencing in university courses. Their data analysis focused on the form as well as on the content of online argumentation. Results concerning the cognitive dimension of online discourse confirmed previous studies. However, regarding the affective and moral (respect) dimensions of online discourse, results were less clear. The authors highlight that the technology, the course design, and the instructor’s actions are equally important to successfully achieve set goals in online learning communities.