
Our Company History

Over 90 years of protection
Milton Pierce used to build his own burglar alarms from salvaged brake drum rims rigged to a striker apparatus. He attached these bells to buildings, covering them with orange wooden crates painted red. A handful of those early alarms are still on buildings in Detroit. Our solutions are more sophisticated today, but we still take pride in our history and will continue the legacy Pierce built.

Milton Pierce Starts Guardian Alarm
June 7, 1930
During the Great Depression and at the age of 15, Milton Pierce started a burglar alarm company in his neighborhood. A few years later, he expanded and purchased Guardian Alarm in Detroit, Michigan.
Adding Guard Services
May 13, 1970
The Guardian Guard Services division is established to provide physical security throughout Michigan and Ohio.
Continued Growth
March 10, 1975
Guardian Alarm is ranked the 14th largest security company in the United States and has continued to be top-ranked.
Armored Cars Begin Patrol
October 25, 1980
The Guardian Armored Security division is established to provide armored car and cash processing services. This division was sold in 2007.
Growth Through Mergers
January 19, 1982
Automatic Alarm and Certified Alarm, both owned by Milton Pierce’s sons Richard and Douglas, merge with Guardian Alarm.
Guarding Our Seniors
November 15, 1999
The Guardian Medical Monitoring division is established to help seniors with personal help buttons, medication management, and wander management devices. The division was sold in 2022.
Growing Down in Florida
April 6, 2004
The Guardian Alarm division expands into Florida through acquisitions of several security companies.
75 Years of Continued Protection
June 7, 2005
Guardian Alarm reaches its 75th year in business and has grown to become one of the largest independently-owned security companies in the United States.
The Legacy Passes On
September 24, 2010
The Guardian Alarm founder, Milton Pierce, passes away at the age of 95. A true pioneer, Pierce set the example with his motto: “Give the customer good service. Take good care of them and they will take care of you.”
Protection Expands in Ohio
July 6, 2011
The Guardian Alarm division expands further into Ohio through the purchase of Complete Protection from Cincinnati Bell.
Securing 85 Years
November 9, 2015
The Guardian Alarm family proudly celebrates our 85th Anniversary and we look forward to continuing the legacy of innovation and industry-leading standards.
A New Chapter Begins
March 2, 2017
The Pierce family sells Guardian Alarm to Certares L.P. & BlackRock, Inc. after 87 years in business.
Detect. Deter. Defend.
March 1, 2019
Guardian Alarm launches Virtual Guardian, a new 24/7 video monitoring service creating real-time remote security solutions with the latest technology, such as live video-voice communication.
Guardian Alarm Expands
April 6, 2022
Guardian Alarm acquires Sievers Security, an independently-owned security company based in Cleveland, OH. This acquisition expands Guardian Alarm’s footprint in Ohio by continuing to be the largest security company in the Midwest.
The Expansion Continues
May 20, 2022
Guardian Alarm acquires Executive Security Consultants, a locally owned and operated security company based in Columbus, OH. Established in 1988, ESC brings along a trusted presence in the Columbus community that Guardian Alarm will help expand for years to come.