According to BizVibe, below are the top 10 security guarding companies in the world, ranked by revenue and growth potential:

1. G4S – founded in 1901, headquarters in UK
2. Securitas AB – founded in 1934, headquarters in Sweden
3. Allied Universal – founded in 1957, headquarters in USA
4. ADT – founded in 1874, headquarters in USA
5. DynCorp – founded in 1946, headquarters in USA
6. GardaWorld – founded in 1984, headquarters in Canada
7. Control Risks – founded in 1975, headquarters in UK
8. The Brink’s Company – founded in 1859, headquarters in USA
9. CACI – founded in 1962, headquarters in USA
10. Booz Allen Hamilton – founded in 1914, headquarters in USA