Background: World Health Organization survey found that 33.3% of Thai students were victims of violent acts, and 46.7%
of those victims were seriously injured from such violence in the past 12 months. The solution to Thailand’s adolescent violence problem mostly focused on prevention programs; all of these programs still lacked an essential element that is surveillance on violence in news, social situations, attitudes, beliefs and environments, which is the first step to solve adolescent violence.
Objective: To develop a surveillance system for decreasing the incidences of physical violence.
Materials and Methods: There were four steps: situation analysis, information delivery, activities creation and a surveillance system synthesis. In the first step, a survey was conducted with 959 students, and then the situation was delivered to the meeting group in the second step. The participatory action research was taken in the third step among the meeting group to create prevention activities for physical violence. The final step, the surveillance system, was the synthesis.
Results: The preventive activities were designed in three areas: violence alarm, violence prevention and violence victim support.
Conclusion: The surveillance system consists of three pillars: Violence Alarm, Avertissement (French for ‘warning’) and Curing System, resulting in “VAC System”.

Keywords: Surveillance system, Youth physical violence, Thailand