Abstract: An interactive GUI is disclosed for viewing and navigating among sets of hierarchical data items displayed on a client device of a user. The GUI displays containers representing and containing respective groups of the hierarchical data items. The containers are displayed in at least two sets, such as rows or columns, where a first set comprises requirement containers representing requirement items, and a second set comprises test containers representing test case items. Annotated edges are displayed between pairs of the containers, where each of the annotated edges indicating a type of relationship between the hierarchical data items in a respective pair of the containers and a percentage of the hierarchical data items in the pair of the containers that have suspect relationships.