We present an empirical study in which we investigated group versus individual performance with collaborative information-visualization environments (CIVEs), the effects of system transparency on users' performance, and the effects of different collaborative settings on CIVE usage. Subjects searched for findings with CIVEs, working either alone, in a collocated dyad using a shared electronic whiteboard, or in a remote dyad using application sharing. Groups answered more questions correctly and took less time with the more transparent CIVE than groups using the less transparent CIVE. We interpret our results to mean that groups have better self-corrective abilities when the system is transparent. We present a stage model to explain the collaborative process of using CIVEs, which accounts for task type, collaborative setting, and system transparency.