Constraint sensitivity refers to the proximity of downstream design to a boundary or a constraint. When downstream design elements are near a constraint, then changes in upstream information could result in significant work in the downstream activity. For example, when a selected pump is near the boundary of its design capacity, a change in flow rate or head loss could make the selected pump no longer acceptable. In this situation, the design process for pump selection would have to begin anew. This is an example of a highly sensitive situation. Another example of a constraint-sensitive situation is the design of piping runs that are located in a pipe gallery. The design of the piping runs is constrained by the dimensions of the pipe gallery. A change in the pipe gallery dimensions could result in significant rework if the pipes are located near the gallery walls.