Defence Systems Limited
- "Who are the sorts of people that would be our clients? Petrochemical companies, mining or mineral extraction companies and their subsidiaries, multinationals, banks, embassies, non-governmental organizations, national and international organizations. Those people who operate in a very dodgy, hostile type of environment." -Stephen Carr-Smith 
- "The benefit of engaging DSL [Defence Systems Limited] Consultants in the formation and training of a police tactical force is that the client is buying the United Kingdom police army model, which is a proven, tried and regularly-tested set of concepts and responses to violent crime and terrorism. DSL instructors bring with them operational experience that has been gained in counter-terrorist operations since 1972, in the UK and in all subsequent major incidents." -Sinclair Dinnen quoting from a DSL document advertising their services. 
Defence Systems Limited (DSL) was one of the earliest Private Military Corporations (PMCs), formed in 1981 by a group of ex-SAS officials riding the swell brought on by Prime Minister Margaret Thatcher's yardsale of Britain's defense industry to cold war warriors of worth. DSL was initially started with private financial support from London bankers, and possibly some Middle East investors. Over the next fifteen years they established a reputation in the security industry and a small fortune, before selling all to Armor Holdings, Inc. in 1997 for $26 million 
What was DSL became ArmorGroup, a one stop shop spot for a variety of products pertaining to defense and riot situations. They then reached out to old foes and brought on ex-KGB commandos when they acquired the Alpha Firm. ; 
DSL has provided protection and training services to a variety of elite niches in the security sector. In addition to major corporations, DSL has received contracts from governments around the world. They guarded the embassies of the United States, South Africa and Switzerland in the Democratic Republic of Congo as well as the embassies of England, Italy, South Africa, Sweden, and the US in Angola. They have provided camps for workers rebuilding a railway line in Mozambique, trained policemen in Somalia, demined areas of the former Yugoslavia and worked with various NGOs.
DSL has provided oil line protection and security force training for oil firms around the world. In the Democratic Republic of Congo they protected the SOCIR oil refinery installations belonging to Congo-SEP, a subsidiary of Belgian Petrofina. In Angola, where they were guarding oil and diamond companies, they were forced to expel 103 of their personnel for violating laws regarding the use of foreign corporate nationals.  Some other past clients include: Amoco, Andarko Petroleum, Bechtel, British Petroleum, Broken Hill Propriety Petroleum, Cambior, Chevron, De Beers, Exxon, Mobile and NGOs CARE and Goal.
- Alastair Morrison: co-founder, was a colonel in the SAS and achieved public fame for his role in the successful rescue of hostages held in an airplane in Mogadishu, Somalia in 1977. After leaving Armor Holdings, he went onto help start Erinys International Ltd. and recently has taken a position at Kroll, Inc. 
- Richard N. Bethell: joined in 1991 , is a former SAS and Scots Guards officer, the current Lord Westbury known also as "Tarzan", was the man in charge of Colombian operations. Bethell, who has started a new company, the Hart Group, is a veteran of the Falkland's War.
- Maj. Gen. Viscount of Brenchley Gilbert Monckton:, a former advisor to the royal family and father to past Daily Standard editor Christopher Monckton and recently revealed MI6 agent Anthony Monckton, was the first chairman of the board 
- David Abbott: Director
- Will Daniell: Ran the DSC office in Bogota
As early as 1990, Richard Bethell was in Colombia protecting oil operations from Marxist rebels, and they have been there since operating through the subsidiary Defence Systems Colombia. They have provided the training of troops for the purposes of securing the 500 mile long OCENSA oil line from rebel attacks, as well as supplies and equipment to carry out the job.
Mark Heathcote of British Petroleum and formerly of the MI6, is the chief of security for BP's operations in the region. In 1997, DSC run security measures saw BP's oil line, the longest in the country, blown up only once. In comparison, Occidental Petroleum's pipeline, the country's second longest, was blown up 65 times. Incidentally, Oxy Petro along with AirScan Inc. and the Colombian Air Force were responsible for dropping a cluster bomb on the town of Santo Domingo the following year.
The improved security may have come at humanitarian costs. DSC trained and supplied soldiers have been implicated in serious acts of repression. The soldiers were from a known right-wing death squad, including a certain Maj. Gen. Herman Guzman Rodriguez, that has been implicated in several massacres.
The extent to which DSC was willing to go in protecting the pipeline included training troops in psychological warfare operations and setting up spy organizations in communities that were not ambivalent to BP's destructive path and inconsideration . Troops armed with equipment brought to them by DSC, OCENSA, and Israeli firm Silver Shadow, were responsible for disposing of dissenters, setting examples for others, and gathering more information under torture  
Said Amnesty International on what has occurred in Colombia: "In the context of the current human rights crisis in Colombia -- in which the Colombian security forces have been responsible for widespread extrajudicial executions, torture and "disappearances" of civilians -- it would be extremely difficult to guarantee that any form of military, security and police training arranged by a private company to protect their own interests is not directly or indirectly contributing to further abuses against the local population."