Fig. 1. Blind users collaborating on an interactive tabletop. Left: after receiving spatial audio feedback about her partners' findings, a user drags her finger to that location. Middle: a user found a relevant object for her partner, proceeding to grab and guide his hand to the object's position. Right: without knowing where their partners are exploring, the users experience unintentional physical contact. Interactive tabletops offer unique collaborative features, particularly their size, geometry, orientation and, more importantly, the ability to support multiuser interaction. Although previous efforts were made to make interactive tabletops accessible to blind people, the potential to use them in collaborative activities remains unexplored. In this paper, we present the design and implementation of a multiuser auditory display for interactive tabletops, supporting three feedback modes that vary on how much information about the partners' actions is conveyed. We conducted a user study with ten blind people to assess the effect of feedback modes on workspace awareness and task performance. Furthermore, we analyze the type of awareness information exchanged and the emergent collaboration strategies. Finally, we provide implications for the design of future tabletop collaborative tools for blind users. CCS Concepts: • Human-centered computing → Accessibility; Empirical studies in accessibility; User studies.