At Sumner Group Defence, we believe that strong leadership is integral to organisational success. We are focused on building a company based on the highest levels of discipline, professional ethos, ethical values, and flawless execution. 

Our executives comprise of seasoned former UK Special Forces and GCHQ leaders, with decades of experience within government, military, academia, and private sector activity. Additionally this group has the benefit of a very experienced board of advisors from which to develop complex corporate governance structures.



David Sumner - Chairman

David is a long term investor with over 20 years of experience in developing successful global business platforms focusing on the healthcare, security & defence, mining and leisure sectors. 


He has been instrumental in seeding, developing and managing the growth of many of the Sumner Group operating businesses and oversaw the public listings of both Sumner Group Mining and Sumner Group Health. He founded Sumner Group in 2018 to consolidate and build upon his business interests.


He has served on numerous private and public company boards in both an executive and non-executive capacity and has a track record of raising capital through debt and equity fundraising.
David founded The Sumner Foundation, a charity specifically set up to benefit disadvantaged students in the UK and also more recently refugees in the Middle East & North Africa.

Max O'Flaherty - Chief Financial Officer

Max joined Sumner Group Defence as Chief Financial Officer in 2020, prior to which he held senior finance positions with Global Student Accommodation (GSA), a global leader in the student accommodation sector with over $3bn AUM.  He has also held senior finance positions with Martello Capital, a private equity company based in Ireland with investments in the Hospitality, Aviation and Technology sectors. 

Having completed his training with EY, Max is a Chartered Accountant with over 10 years’ experience in various finance roles across Ireland, U.A.E. and the U.K. He also holds a Bachelor's Degree of Commerce from University College Dublin, Ireland.

General The Lord Richards of Herstmonceux GCB CBE DSO DL, Advisor to the Board

General Richards joined as an advisor to the board of Sumner Group in 2020.


Having commanded operations in East Timor, Sierra Leone, and Afghanistan, General Richards went on to command NATO forces in Afghanistan during the Alliance’s expansion of responsibility across the whole country.  He subsequently went on to command the British Army. 


In 2010 he became Chief of the Defence Staff, the professional head of Britain’s armed forces and their strategic commander as well as the Prime Minister’s military adviser and a member of the National Security Council.  He retired in July 2013.  


His UK operational awards include a Mention in Despatches, Commander of the British Empire, Distinguished Service Order and Knight Commander of the Bath; the first officer to receive an operational knighthood since World War 2.  In 2011 he received the annual Churchillian Award for leadership.  He was created Baron Richards of Herstmonceux in February 2014 and now sits in the House of Lords.  


Amongst other appointments he is a visiting Professor of Exeter University and an Honorary Fellow of both King’s College London and Cardiff University. He is Executive Chairman of Equilibrium Global the geo-strategic advisory company and actively involved with a number of charities, especially the Royal Commonwealth Ex-Services League of which he is the Grand President.  His autobiography Taking Command was published in October 2014.

Robert Hannigan, Advisor to the Board

Robert Hannigan joined as an advisor to the board of Sumner Group in 2020.

Robert was at the centre of UK national security for twenty years. He was the Prime Minister’s Security Adviser from 2007-10 and a member of the National Security Council and the Joint Intelligence Committee. Prior to that, he worked as principal adviser to Tony Blair on the Northern Ireland peace process. 


As Director of GCHQ, the UK’s largest intelligence and cyber agency, he established the new National Cyber Security Centre, bringing together government and private sector to improve the nation’s cyber security.


Robert is a leading authority on cyber security, cyber conflict and the application of technology in national security and contributes regularly to the Financial Times, BBC and other media. He chairs a UK Government-funded accelerator for cyber scale-ups and was a member of the Defence Innovation Advisory Panel. 


Robert is a Senior Fellow of Harvard’s Belfer Centre for Science and International Affairs, the Institution of Engineering & Technology and RUSI, and an Honorary Fellow of Wadham College, Oxford. He was awarded the US Intelligence Distinguished Public Service Medal in 2017 and honoured by Queen Elizabeth for services to UK national security in 2013.

Major General (retired) Nick Ashmore CB OBE, Advisor to The Board

Nick Ashmore joined as an advisor to the board of Sumner Group in 2020.

Nick joined the British Army in 1984.  Having spent his formative years at regimental duty, in both the UK and Germany, he went on to command 3rd Regiment Royal Horse Artillery from 2001 to 2004, a period which included a UN tour in Cyprus and the invasion of Iraq in 2003, for which he was appointed OBE.  He held four staff appointments in the Ministry of Defence and, as a Brigadier, was Director Plans in Army Headquarters. 


On promotion to Major General in 2011, Nick was the first Director Strategy and Plans in the then newly-formed Defence Infrastructure Organisation (DIO), responsible for Defence basing and infrastructure planning and programming, including the Defence Infrastructure Programme, the Defence Estate Strategy and the Army Basing Programme 


In 2015, he was appointed Military Secretary, leading the Army Personnel Centre in Glasgow, and responsible for career and talent management for the British Army.  He was the first Military Secretary to also hold the title of General Officer Scotland, as the senior serving Army officer in Scotland.  He was appointed CB in 2016.