Gareth Tennant

Gareth Tennant is a cybersecurity and intelligence expert with over a decade of operational experience at the highest levels of the UK Armed Forces. Drawing on 14 years of service in the Royal Marines, Gareth has built a reputation as a trusted authority in managing risk, decision-making under pressure, and navigating complex information environments. His military background has given him a deep understanding of how to use intelligence and data to gain strategic advantage – a skillset that translates directly to the cybersecurity challenges facing modern organisations.

During his time in the military, Gareth held a series of high-impact roles, including Decision Support/ISR Manager for the Royal Marines and wider Defence, where he led intelligence and surveillance operations in support of UK and allied forces. He worked across the UK military and with international partners to deliver intelligence in high-stakes environments. As Head of ISR and Cyber at 360iSR Ltd, he directed cybersecurity strategy and implementation, helping organisations understand and defend against emerging threats. Gareth was also a key contributor to the development of the Royal Navy’s Information Superiority Policy and NATO doctrine on intelligence operations, placing him at the forefront of military cyber and intelligence strategy.

Since leaving full-time service, Gareth has continued to support governments and businesses through his work as Founder and Director of Decision Advantage, a consultancy focused on strategic decision-making, data exploitation, and cybersecurity. He also works with MAIAR Ltd and serves as an advisor to the Future Strategy Club, where he applies his military-honed skills to commercial challenges. His academic credentials include an MSc (Distinction) in Intelligence, Surveillance and Reconnaissance (ISR) Management, a BEng in Command, Control and Communication Information Systems, and a Level 8 Diploma in Strategic Management and Leadership from Alliance Manchester Business School.

As a keynote speaker, Gareth delivers compelling talks on cybersecurity, leadership and decision-making, drawing parallels between military operations and business environments. He offers practical strategies to overcome information overload, improve cyber resilience, and lead effectively in high-pressure situations. Whether speaking to senior executives, tech leaders, or security professionals, Gareth brings a clear-eyed, experience-led perspective that helps audiences think differently about risk, information, and innovation in today’s digital world.