Reliant Systems of Southwestern Pennsylvania was formed in 1982 by Larry J. Cole. We are a security company providing the installation, service, and monitoring of burglar alarm systems and fire alarm systems both residentially and commercially. Reliant Systems also installs and services access control systems and closed circuit television systems. Although formed in 1982 as a sole proprietorship, owner Larry Cole chose to work for another security company, Firm Security Systems, for twenty years.

Reliant Systems became an active business again in July 2004 when Firm Security Systems was acquired by a larger company.

In the fall of 2007, a new office was opened in Elizabethtown, PA under the partnership of Mark Costa. Reliant Systems East offers the same products and services as Reliant Systems.

Reliant Systems has shown continued growth over the years. In 2008, Reliant Systems purchased CrimeTech Security. This was followed by the acquisitions of Titan Security and Bob's Lock in 2009, and Tri-State Security in 2010.