WHO WE ARE
Your protective security partner.
Manned guarding, mobile patrols, CCTV, executive protection and event security, with a specialist focus on crowd management, behavioural detection and emergency preparedness. Led by people who have served.
WHAT WE STAND FOR
Not just officers on a gate. People who prepare, train and show up.
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Officers
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Events Covered
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Years of Service
HOW WE OPERATE
The DIAMA Standard
Four commitments that run through every site, every shift, every client.
We train
Licensed, current and drilled in Martyn's Law, behavioural detection and emergency procedures.
01
We prepare
Risk assessments and site plans before the first officer arrives, not after the first incident.
02
We protect
People, venues and events, with visible, professional officers who lead from the front.
03
We give back
Training places, sponsorship and support for veterans and the Armed Forces community.
04
OUR MISSION
Safer, more resilient places for the people in them.
Intelligent, adaptable security that doesn't just protect, it strengthens the safety and resilience of the people, properties and operations entrusted to us.
CORE VALUES
Integrity
Honest, ethical conduct in everything we do.
Professionalism
Reliable, top-tier service clients can depend on.
Innovation
Staying ahead of security advances and threats.
Customer focus
We listen, adapt and tailor to exceed expectations.
OUR PEOPLE
Meet the team who make it all come together.
The people setting the standard, leading with the discipline, judgement and experience that shape how every officer operates, on every site, every time.
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Barney Barnett
Managing Director
Former Royal Marines Commando. 18 years’ service, 28+ years in security. Knows what pressure demands, because he’s lived it. Sets the standard every officer follows.
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Glen Clark (Clarky) M.ISRM, M.IPSA
Head of Operations
Former British Army. Close Protection Officer. Experienced Crowd Manager with an operational background spanning Excel London and Arsenal Football Club.
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Nick Lewis
Senior Security Operations Manager
Served 20+ years in high-threat, UHNW environments. Knows what complex operations demand, because he's run them himself. Sets the tone every officer follows on the ground.
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Siddiq Mohammed
Marketing & Commercial Manager
Brings creativity and commercial awareness to DIAMA. Works hard behind the scenes, supports colleagues and solves problems. A trusted teammate who steps up when it counts.
Callum Chesters
Security Project Manager
Served 10 years in the military across worldwide deployments. Knows what close protection demands, because he's worked it himself. Sets the standard every shift is built on.
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Oliver Denton-Powell
Assistant Operations Manager
Oliver brings eight years of Army service and private security experience. He works calmly and discreetly under pressure. He upholds DIAMA’s standards of professionalism and confidentiality.
ACCREDITATION
Accreditations & compliance
Diama Security Limited holds SIA Approved Contractor status for the provision of Security Guarding services.
Supporting Royal Marines, veterans and their families.
Honouring our commitment to the Armed Forces
Supporting the DWP’s drive to get people into work.
Proud member of the City Security Council, working with police to keep the City safer.
Gold Member - Verified for health & safety, financial and environmental standards. PAS 91 compliant.
COP 119 Certified. Staff vetted to BS 7858, ensuring compliant and competent personnel.
Committed to inclusive hiring and supporting disabled employees.
Member of the International Institute of Risk & Safety Management.
Supporting security professionals through industry expertise, best practice, and professional standards.
Recognised awarding body for our security training and qualifications.
Committed to maintaining consistent quality and the highest standards across all our services.
Supporting Imperial College London with asset protection, event security, manned guarding and training.
Your Trusted Security Partner
A veteran-led British security business protecting people, venues and events from Canary Wharf to the front gate.