Abstract In this paper the As-Is model of the organizational affairs process of the NIORDC (National Iranian Oil Refining and Distribution Company) was drawn by the use of BPMN modeling tool, and then its simulation model was modeled by using SIMPROCESS simulation software and relative parameters were defined. Necessary scheduling in defining simulation parameters were extracted and set according to available organizational documents and archives. Afterwards, justification and verification of simulation models were tested by using statistical tests. In the next stage, several reengineering scenarios were suggested and designed according to BPR rules, experts' viewpoints, brainstorming sessions, and the facts found during project implementation. These scenarios were modeled by using BPMN modeling tool, and then their simulation models were designed. Since these scenarios are about the future situation of the process, only some justification and verification steps of simulation models were considered. Finally, on the basis of defined indicators in the beginning of the project, values of them were calculated for each scenario and each one was analyzed on the basis of cost-benefit analysis. At last, these scenarios were ranked by using AHP method and their scores were counted in order to suggest to the management.

Abstract Emergence of different approaches in the field of Organizational Development has raised the question that which approach Fits which organizational conditions for achieving Organizational Development. In order to answer this question Organizational Development approaches are divided into three categories. The first category is composed of those approaches in which radical and top-down changes along with using information technology are emphasized. Business Process Reengineering is the typical approach in this group. Those approaches that focus on partial moderate changes and give importance to quality of production and services fall in the second category. Total Quality Management can be labled as a typical in this group. The third category includes the approaches in which gradual change through organizational learning makes an organization prepared to meet environmental changes. Learning Organization can suitably referred to as a typical approach in this group. Having applied the technique of Critical Success Factor (CSF) to the corporate’s states of financial, market and customer satisfaction, we proposed a model to fit situational factors to effective organizational approaches. This model was emprically tested in serveral Iranian enterprises.