Aspect orientation encompasses a set of techniques that improve modularity through the phases of software development. So far, aspect orientation is better known as a technology at the programming level. In this book we intend to contribute to the understanding of aspect orientation at the earlier phases of requirements and architecture design. We explore the idea that requirements artifacts are better understood and concerns are better separated by detecting crosscutting concerns with aspect-oriented techniques. We provide an overview on early aspect approaches, on the concepts of aspect orientation in requirements and illustrate a method for an improved separation of concerns at the hand of an online garment store case study. Altogether, in this work we endorse the notion that early identification, description and proper documentation of aspects improves requirements specification and analysis.