Agent–oriented conceptual modeling notations such as i* represents an interesting approach for modeling early phase requirements which includes organizational contexts, stakeholder intentions and rationale. On the other hand, Unified Modeling Language (UML) is suitable for later phases of requirement capture which usually focus on completeness, consistency, and automated verification of functional requirements for the new system. In this paper, we propose a methodology to facilitate and support the combined use of notation for modeling requirement engineering process in a synergistic fashion. For organizational modeling/early phase requirements capturing we use the i* modeling framework that describes the organizational relationships among various actors and their rationales. For late (functional) requirements specification, we rely on UML Activity Diagram.