There are many good reasons why organizations should perform software architecture reconstructions. However, few organizations are willing to pay for the effort. Software architecture reconstruction must be viewed not as an effort on its own but as a contribution in a broader technical context, such as the streamlining of products into a product line or the modernization of systems that hit their architectural borders. In these contexts software architects frequently need to reason about existing systems, for example to lower adoption and technical barriers for new technology approaches. We propose a Quality Attribute Driven Software Architecture Reconstruction (QADSAR) approach where this kind of reasoning is driven by the analysis of quality attribute scenarios. This paper introduces a quality attribute driven perspective on software architecture reconstruction. It presents a technical reasoning framework and illuminates the information that is required from the reconstruction process to link the knowledge gained back to the business goals of an organization. The paper illustrates the techniques by presenting a real-world case study.