Quality of software is one of the major issues in software intensive systems. Quality is especially important in software product families that exploit the same architecture and components in a set of products. Therefore, the aim is to evaluate quality of software as early as possible, i.e. from the descriptions of software architecture. Evolution qualities such as maintainability and extensibility can be evaluated in the development phase. Others, like reliability and performance, are intertwined with the functionality of a system and thus observable only at run-time. In order to evaluate quality at the architectural level, quality properties have to be defined and represented in architectural models, derived from requirements specifications of a product (family). QADA® supports traceability of quality requirements to designs, representing variability and quality requirements in architectural models, and evaluation of quality properties from the architecture models.