We envision a new class of methods, constituting what we call a cooperative design methodology, to support group decision making in design practice. As a first step, we model the cooperative design process as a multicriteria, multilevel decision problem and focus on understanding the relationships between design structure and decision strategies. In this paper, we present methods to characterize sequential decision strategies. We first introduce the notion of Quality Loss to quantify the loss of design freedom in the downstream stages of a sequential scheme. Towards identifying the sequence with the lowest quality loss (the “optimal sequence”), which is of practical significance in the design of time-critical products, we partition design variables into exclusive groups based on their connectivities. Next, the sensitivities and connectivities are combined to characterize invariant design decisions. Sufficient conditions, relating exclusive group structure to invariant decisions, are presented to reduce the complexity of identifying the optimal sequence. These ideas are illustrated using a dc motor design example.