Group awareness refers to being informed about group members or a group. It is an important prerequisite for successful collaboration and can be supported by group awareness tools that collect, transform, and present behavioral, social, and cognitive information. Such tools not only provide learners with information on their learning partners but also comprise additional functions that can foster individual and collaborative learning processes. CSCL-related group awareness research repeatedly identified promising effects of group awareness tools on learning processes and outcomes for a number of educational settings. However, few studies have tried to pinpoint these effects or investigated specific aspects of the tool design. Future research faces the task of extracting precise tool mechanisms to provide efficient and adaptive CSCL support tailored to specific settings, tasks, and learners.