Object-oriented analysis and design have been more concerned with system functionality, neglecting non-functional aspects; the result is code which is tangled and difficult to maintain, contradicting main principles of object orientation. Aspect Oriented Software Development (AOSD) proposes the early specification of non-functional requirements. However, a standard and homogenous vision of the AOSD terminology is still missing. The goal of this work is to integrate AOSD concepts, classic requirements engineering notions, and the new standard ISO/IEC 25030 on software quality requirements.The main result of this study is the REASQ (REquirements, Aspects and Software Quality) conceptual model, expressed in UML. All the modelling concepts are formalized into three related ontologies, representing the ambits of aspect-orientation, software quality and requirements engineering. The ontologies can be used as an umbrella to specify quality requirements in aspect-oriented engineering processe...