We describe a new information structure composed of multiple intersecting hierarchies, which we call a Polyarchy. Visualizing polyarchies enables use of novel views for discovery of relationships which are very difficult using existing hierarchy visualization tools. This paper will describe the visualization design and system architecture challenges as well as our current solutions. Visual Pivot is a novel web-based polyarchy visualization technique, supported by a “polyarchy server” implemented with a Mid-Tier Cache architecture. A series of five user studies guided iterative design of Visual Pivot. Finally, we discuss the effectiveness of animation in Visual Pivot.