Established in 1970, the Company researched, developed, manufactured and sold a "Hands-free" method of access control to safeguard secure areas within buildings. Having pioneered this technique, the Company consolidated its position in the field by expanding into perimeter access control systems and integrated surveillance equipment.

Today, Mastiff includes a large number of major UK companies as well as Government offices in its customer base. These prestigious organisations choose Mastiff to provide security solutions, along with a full engineering back-up team for maintenance and system enhancements.

Starting out in Leatherhead, Surrey, as Lewis Security Systems, (named after one of its founders), the Company subsequently changed its name to Mastiff Security Systems Limited in 1977 in order to take full advantage of the growing popularity of its trade name, "Mastiff", an acronym for