The Centers for Disease Control and Prevention use a three-tiered model of prevention:
Primary prevention: Primary prevention takes place BEFORE violence initially occurs. It involves programs and strategies designed to reduce the factors that put people at risk for experiencing violence. Or, they encourage the factors that protect or buffer people from violence.
Secondary prevention: Secondary prevention takes place immediately AFTER a violent event. It deals with the short-term consequences and focuses on the immediate needs of the victim—such as emergency services or medical care.
Tertiary prevention: Tertiary prevention is a long-term approach AFTER a violent event has occurred. Efforts may include rehabilitation of the perpetrator, or social services to lessen emotional trauma to the victim.