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Executive Committee

Andrew Belshaw

Skills and experience

With a background as a chartered accountant, Andrew has worked in both audit and corporate finance at Deloitte LLP and Ernst & Young, specialising in providing advice to a wide range of clients in the technology sector. After leaving private practice, Andrew worked alongside the commercial director in a new business development role at Xansa plc before joining Gamma in 2007.

Andrew has a degree in maths from St John’s College, Cambridge and gained an MBA from Warwick Business School. He is a Fellow of the Institute of Chartered Accountants in England and Wales.

Andrew was promoted to CEO in 2022 having formally been Gamma’s interim CEO and former CFO.

Other roles


Bill Castell

Skills and experience

Bill joined Gamma in 2022 from OVO Energy, where he held the role of CFO. Before joining OVO Energy in 2020, Bill spent three years at Virgin Media which he joined as deputy CFO and later became acting CFO. From 2005 to 2017, Bill was at Barclays Bank where he held several senior finance roles including CFO at Barclays Corporate Bank and CFO of Barclaycard Europe.

Bill started his career as an officer in the British Army and, as a qualified accountant (FCA), has worked in the technology, media and telecom sector as an auditor at Deloitte and investment banker with Goldman Sachs.
Bill is a Fellow of the Institute of Chartered Accountants in England and Wales.

Other roles

Bill is also a non-executive director of the Financial Ombudsman Service.

Chris Bradford

Chris joined Gamma in 2021 to lead the company’s people and engagement strategy, having worked as a board level HR leader, and subsequently as a consultant, on business transformation and organisation design programmes for organisations across multiple sectors and geographies such as Vodafone, Equinix, Aviva Investors, the Financial Ombudsman Association, and the British Olympic Association.

She holds a first-class honours degree in English from Leeds University.

Chris Wade

Chris joined Gamma in December 2020 from Aptitude Software where he held the role of chief product officer. Prior to this, Chris held several leadership roles in strategy, product management and marketing in several different operating businesses within The Sage Group plc, one of the leading providers of business management solutions to SMEs globally.

Chris holds a MPhys in physics from Jesus College, Oxford.

Colin Lees

Colin joined Gamma in January 2024 from Openreach where he spent 5 years as chief technology and information officer. During this time, he designed and built the IT & network platforms which underpinned the UK’s largest full fibre rollout.

Prior to this Colin held several leadership roles at the BT Group, including CTO of the BT Group consumer & business divisions driving IT transformation and launching a range of new products – including business VoIP platforms, BT Sport and the first BT Business hub with integrated fixed and mobile services.

Colin is a graduate of Queen’s University Belfast with a degree in computer science.

David Macfarlane

David joined Gamma in 2012 following Gamma’s acquisition of his last start-up communications business, Varidion Limited, and built Gamma’s direct go-to-market organisation. He is responsible for driving growth of our Enterprise and Public Sector market share across Europe as Managing Director of our Gamma Enterprise business unit.

A passionate advocate for technology disruption and an engineer by trade, David has built, owned, and run multiple IT and Communication service providers that have challenged and changed how organisations buy and use business technology.

Before this, David had senior IT roles in the NHS, a large city law firm and a Brokerage House and was the co-founder and CTO at Sirocom Limited and Group CTO at Azzurri Communications.

John Murphy

In June 2024, John was appointed as Managing Director – Gamma Business, having previously been appointed as COO in 2023.

John joined Gamma in 2011 bringing more than 15 years of experience delivering successful transformation programmes in financial services, utilities and telecoms sectors. After 8 years as a change management consultant, he then took an operational role for Gamma in 2013 and since that time has worked in various senior roles, overseeing customer services to Channel Partners and Service Providers.

Gerben Wijbenga

Gerben joined Gamma in August 2020 taking full responsibility for business activities across the Netherlands and Belgium. In 2023, he combined this activity with running our German business becoming Gamma’s CEO of Northern Europe.

Gerben started his career at KPN where he worked for 10 years. After KPN Gerben was directeur général at Simyo France and CEO at Ortel Mobile, an MVNO with activities in six countries. Gerben spent time at Telefonica (Deutschland) and Tele2 (The Netherlands), where he was the CEO of Blau Mobilfunk and managing director of the consumer market, respectively. In his most recent role before joining Gamma, Gerben was CEO at Lebara Deutschland, a market-leading MVNO based in Düsseldorf.

Rachael Matzopoulos

Rachael was appointed as company secretary of Gamma in January 2023 having previously gained governance experience in a variety of large multinational listed groups, most recently at GSK plc and Videndum plc. As company secretary, she is responsible for advising the board, through the Chair, on all governance matters.

She is a Fellow of the Chartered Governance Institute and has a masters degree in business and management from The University of Glasgow.

Xavier Casajoana

Xavier joined Gamma in April 2020 following Gamma’s acquisition of VozTelecom.

After more than 10 years in information systems management, Xavier joined Worldonline as director of information systems. After merging with Tiscali, he became director of the business services division and later held the role of general manager for Spain. In February 2003, he co-founded VozTelecom as the CEO.

He has a degree in computer science from UPC and a master in business and technology from the URL, as well specialised degrees in marketing by ESADE and management by IESE.