Three semantic traits are considered central in the design of interfaces for scheduling: (1) expressive richness, (2) dependency constraints and (3) global homogeneity. These traits are exploited by diagrammatic representations that ?structurally integrate? systems of domain relations through analogous systems of diagrammatic relations. These traits are discussed in relation to ROLLOUT - a prototype representational system for bakery planning and scheduling. This article provides a semantic evaluation of ROLLOUT in terms of these representational traits and proposes explanations of how these traits lead to increased cognitive support in scheduling activities.