​The Freeway Service Patrol (FSP) is a joint program provided by the California Department of Transportation (Caltrans), the California Highway Patrol (CHP) and the local transportation agency. The FSP program is a free service of privately owned tow trucks that patrol designated routes on congested urban California freeways. Typically, FSP operates Monday through Friday during peak commute hours, and all day in pre-designated freeway construction zones. In heavily congested freeway corridors it is becoming more commonplace for FSP to operate during the midday and on weekends/holidays in addition to the weekday peak period service.

​The goal of the FSP is to maximize the effectiveness of the freeway transportation system. The FSP is a congestion management tool which strategically addresses commute traffic pattern problems. Deployment of the FSP trucks is driven by congestion patterns in major metropolitan areas. It is necessary for the FSP program to respond immediately to changing or increasing needs for impediment mitigation.

The goal is accomplished by the expeditious removal of disabled/stranded vehicles from the freeway. Removing obstructions on the freeways as rapidly as possible has a positive impact on traffic volumes by eliminating problems which contribute to non-recurrent congestion. Each year, the FSP program assists approximately 650,000 motorists on California's highway system.
Rapid removal of freeway obstructions also reduces fuel consumption and minimizes automobile emissions by reducing the time vehicles spend idling in stopped traffic. Currently, over 350 tow trucks operated by CHP-trained, certified and supervised drivers, patrol in excess of 1,750 miles of the most congested freeways in California.