In this paper we report partial progress of our research about system nsion. We used levels of abstraction and decomposition strategy to reduce system complexity. Concept Relationship Oriented methodology is one of its result, the methodology can be used, to develop new artifact for reverse engineering. There are two significant reported activities: searching Concept Representation, and searching Structure of Concept. Searching Concept Representation was a process, to find a representation, proper or might exist less depend on artifact types (for example: unique concepts). In this stage cy on level of abstraction still tight, but at the second stage we found the representation, Structure of Concept.