Abstract
OCD (Operational Concept Document) is very important in system development. To develop OCD we should answer questions about, what template to use, what is the overall process to develop OCD, what kinds of diagrams we should use and how can we validate the OCD. To answer about the template we compared tow industrial guide on operational concept development and tailored it. For development process, we proposed a comprehensive process which satisfies the requirements of the project context. For use of proper diagram, we analyzed many kinds of diagrams used in representing behavior of system and choose some diagrams which best fit for our purpose. Finally we established validation criteria for operational scenario and requirement texts in operational concept documents.