1. ABSTRACT 2. INTRODUCTION 3. HEROIN-CRIME SYSTEM DESCRIPTION 4. CONCEPTUALIZATION STEPS 4.1 PURPOSE OF THE MODEL 4.2 MODEL BOUNDARY 4.3 REFERENCE MODES 4.4 BASIC MECHANISMS 5. CONCEPTUALIZATION EXERCISE 6. CONCEPTUALIZATION EXERCISE SOLUTION 7. APPENDIX A: MODELING WORKSHEET 8. APPENDIX B: RELATED READINGS

This paper is the first in the series and explains the first stage of the model building process called conceptualization. The paper examines in depth the following steps of conceptualization: 1. Define the purpose of the model. 2. Define the model boundary and identify key variables. 3. Describe the behavior or draw the reference modes of the key variables. 4. Diagram the basic mechanisms, the feedback loops, of the system

It can be used for the definiton of the final project,also it's a good start to clarify doubts in the conceptualization part of the project