Web 2.0 represents a shift from static to highly dynamic, participative, and collaborative Web. However, most of Rich Internet Applications (RIAs) are still not accessible; as a consequence, universal participation is still far from being a reality. Providing accessible means for “awareness of others” (i.e. a perception of the activities of others in the system) is essential in RIAs to enable collaboration among all users. This chapter explores, through a systematic literature review, studies approaching the topic in accessible collaborative RIAs. The authors also identify the technologies proposed, extended, or used by those studies. As results they characterize the studies in the area and clarify the state-of-the-art of technologies for supporting awareness of others. Finally, the authors propose a set of guidelines aiming at supporting the design of mechanisms for awareness of others in collaborative RIAs.