In this chapter, the literature of online collaborative learning (OCL) is extensively reviewed for contributions to evaluation. This review presents a new taxonomy for evaluation studies of OCL, identifying studies of students’ experiences, studies of instructional methods and sociocultural studies. Studies that focus on evaluating students’ experiences engage approaches from phenomenology and ethnography to explore students’ perceptions of collaborative learning. Instructional method studies attend to evaluation of the tools, techniques and outcomes. Sociocultural studies emphasize the socially constructed nature of the teaching and learning processes and are concerned, therefore, with evaluation in its social context. The sociocultural studies fall broadly into three clusters: pedagogical studies, linguistic studies and cross-cultural studies. The analysis highlights the need for theory-driven empirical evaluation of OCL. Accordingly, three theoretical frameworks for OCL evaluation are discussed. Emphasis is placed on a Communicative Model of Collaborative Learning, developed from Habermas’ Theory of Communicative Action, for its contribution to evaluating what takes place within the social context of students’ communicative practices that is productive of collaborative learning in an online environment.