OUR
people
Security is a heavily regulated industry. Qualifications, accreditations and the right kind of experience are essential. No credible security company will be without them. We’re no different as you will see from our Quality Policy. What sets Executive Security Solutions apart is its people. We are a privately owned, family business. We are headed up by husband and wife team John and Debbie Cassie and their “family first” approach dictates not only the kinds of people who want to work at ESS but also the feel of the service we offer.
Our strong family values are at the core of the service we provide. We focus on nurturing all relationships, both internally and externally. We operate with the utmost transparency and loyalty and strive for excellence in everything we do. Our teams can often become part of your day-to-day life. Our focus on maintaining family values means they will always fit in.
EXECUTIVE TEAM
JOHN CASSIE MSyl
CHIEF EXECUTIVE OFFICER
John Cassie, former military, is the founder of Executive Security Solutions Limited (ESS). With over 27 years of experience in the private security sector, particularly serving Ultra-High-Net-Worth (UHNW) clients, John brings unrivalled expertise and dedication to ESS. He began his private security career in close protection and surveillance, later expanding his focus to develop a holistic approach to residential security. John has built all-encompassing, bespoke security solutions for luxury estates and high-value properties, integrating advanced electronic systems to enhance security measures.
He collaborates closely with industry professionals in architecture, design, and construction to ensure that security solutions are seamlessly embedded into large-scale projects worldwide. His commitment to excellence is exemplified by his longest-standing client, who has entrusted John’s expertise for over two decades.
His extensive experience ensures that ESS consistently delivers top-tier personal protection services, security consultancy, risk management and discreet security services to its clientele. John is a Corporate Partner of The Security Institute, and a member of ASIS International and a supporter of Historic Houses.
DEBBIE CASSIE MSyl, CSBM, CIWM
CHIEF OPERATING OFFICER
Debbie Cassie is an accomplished leader in the private security sector, known for her hands-on, results-driven approach. With a deep understanding of delivering bespoke security services to ultra-high-net-worth individuals and private clients, she combines strategic planning, operational expertise, and team leadership to drive sustainable growth at Executive Security Solutions Ltd (ESS).
As the integrator at ESS, Debbie oversees Finance, Operations, HR, Risk, IT, Marketing, and Business Development, bringing her extensive board-level and business management experience to shape the company’s strategic direction. Her leadership has been instrumental in streamlining processes, embracing new technologies, and driving efficiencies, building a solid foundation for sustainable growth. With a strong focus on quality, compliance, and collaboration, Debbie ensures that ESS consistently meets the highest standards of service delivery while staying competitive in a rapidly evolving industry. A passionate advocate for loyalty, honesty, and trust, she has embedded these values into the company’s culture.
Committed to the Armed Forces Covenant, she takes pride in supporting ex-veterans through employment opportunities. Debbie is also a Corporate Partner of The Security Institute, a member of ASIS International, and a supporter of Historic Houses, continually striving to raise standards and improve working conditions within the UK’s security industry.
GRAHAM SUMMERS ASyl
OPERATIONS DIRECTOR
Graham brings over 23 years of distinguished service with the Metropolitan Police, including 12 years in the Royalty and Specialist Protection (RaSP) command. During this time, he played a pivotal role in safeguarding senior members of the British Royal Family, initially as part of the elite Special Escort Group (SEG) and later in Close Protection. His expertise and dedication led to his appointment as a Personal Protection Officer, where he managed global security for high-profile individuals in both private and official capacities.
In 2020, Graham transitioned to the private sector, taking on the role of Head of Security for an ultra-high-net-worth client. There, he successfully developed and implemented comprehensive security and operational protocols for the client’s family, properties, and assets.
In 2023, Graham joined the ESS Executive Team, bringing his extensive expertise in close protection, operations, and project management to further strengthen the team’s capabilities to support the operational growth of the company.
TRACEY BIRCH ASyl, Assoc CIPD, ACIPP
BUSINESS SUPPORT MANAGER
Tracey joined Executive Security Solutions (ESS) in September 2023 as the Business Support Officer and was promoted to Business Support Manager in February 2024. She provides comprehensive administrative support across HR, Operations, IT, Finance, and Business Development, ensuring ESS meets its statutory and legal obligations.
With over two decades of experience in HR, payroll, and administrative support, Tracey brings a wealth of knowledge and expertise. An Associate Member of both CIPD and CIPP, she is known for her exceptional communication skills, attention to detail, and commitment to high standards. Tracey is also a certified Mental Health First Aider, reflecting her passion for promoting mental health and well-being in the workplace.