3700 Delta Fair Blvd
Suite 202A, Antioch, CA 94509
Phone: (818) 650-2209

23452 Lyons Avenue 200A
Newhall, CA 91321

1426 University Ave. Suite 104
Riverside, CA 92507

Our Services

Brosnan Security provides security services and guards in California. Brosnan is full-service investigative, protective and intelligence firm to a global network of clients. Headquartered in New York City, with branch locations in multiple states, Brosnan is one of the largest privately held providers of technology-driven security services. With more than 500 years of law enforcement experience, Brosnan understands the law, and more importantly, law breakers. We protect your people, property and assets for aggressive risk mitigation strategies and technologies. Brosnan is a technology-driven best-in-class security provider.

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