This book systematically identifies the lack of methodological support for development of requirements and software architecture in the state-of-the-art. To overcome this deficiency, the QuaDRA framework is proposed as a problem-oriented approach. It provides an instantiation of the Twin Peaks model for supporting the intertwining relationship of requirements and software architecture. QuaDRA includes several structured methods which guide software engineers in quality- and pattern-based co-development of requirements and early design alternatives in an iterative and concurrent manner. Contents Context Elicitation Problem Analysis Architectural Pattern Selection Application Domain Knowledge Analysis Requirements Interaction Analysis Software Architecture Alternatives Derivation Evaluation Problem-Oriented Requirements Engineering for Software Product Lines Target Groups Students in the software engineering discipline Researchers who aim at investigating the relationship between requirements engineering and software architecture Practitioners such as software engineers working in the areas of requirements engineering and software architecture design The Author Ms. Azadeh Alebrahim is currently working as an IT consultant. She advises the customers on IT Service Management, process optimization, restructuring the IT organization, and digitalization