Issues Dealing with Non-Functional Requirements across the Contractual Divide

Agreement on Non-Functional Requirements between customer and supplier is crucial to a successful IT solution delivery project. In an ideal world, stakeholders and architects cooperate to achieve their common goals in a win-win situation. In a commercial setting, however, one dominant feature often introduces powerful forces from outside the technical realm. That feature is the customer/supplier relationship, usually formalized in bidding rules or as a delivery contract. Formal customer/supplier relationships often place severe limitations on information exchange between stakeholders and architects. In this paper, we explore the effect of such limitations on the interaction of architectural design with the quantification of Non-Functional Requirements, and explore a number of avenues to deal with them.