Our Businesses

We are an international value-add distribution Group, organised across three sectors: Controls, Seals and Life Sciences.

Our value-add services are delivered alongside our products, which include: wire & cable, connectors, fasteners and adhesives; seals, gaskets, hose and fluid power sealing products; surgical and diagnostic equipment, consumables and instrumentation. We operate in core geographies of North America, Continental Europe, UK and Australia.


Empowered by a decentralised culture

We believe in ownership at the front of the organisation - close to our customers, our colleagues, our suppliers and our markets. Our business leaders are empowered to lead their businesses and take accountability for their success. 

At the same time, our businesses benefit from being part of a large, multinational Group - creating leadership networks, collaborating, sharing best practice, and having access to Group resources.

Our businesses

Our businesses deliver the solutions and products that bring our purpose to life. 

They distribute specialised products, which are critical components in our customers' value chains. These products are low cost, relative to overall spend, and part of operating expenses, rather than capital budgets. These products come in a 'service wrapper'. That service wrapper might be in the form of deep technical support, proprietary material compounds, innovative and cost-saving kitting or packaging solutions, or responsive customer service. 

Our history

Diploma was founded in 1931 by Gertrude Mary Sellick and started its life as a 'bagwash' shop. It was listed on the London Stock Exchange in 1960 and changed its name to Diploma Investments in 1966. 

By 1969, the Group was starting to acquire industrial companies and became a market-leading distributor of electronic components, building products and specialist steels. 

In 1978 the Group changed its name again, this time to Diploma PLC, and in 1982 it re-registered as a public company. 

During the 1990s, and under the management of Group CEO, Bruce Thompson, who joined in 1994, a new acquisition programme was introduced and the Group underwent a radical restructuring. During this time, the Group acquired Rayfast and Hercules.

Nigel Lingwood joined the Group as CFO in 2001. Nigel and Bruce led the Group together until Bruce retired in 2018, followed by Nigel in 2020. During that time, the Group acquired a number of businesses, including Somagen Diagnostics, HKX, M Seals, Kubo, FS Cables and Abacus. 

Johnny Thomson joined Diploma as Group CEO in 2019. He has overseen the acceleration of the Group's strategy and its ongoing and successful growth and scale. In that time the Group has grown from a revenue of £485m in FY18 to where it is today. Under Johnny's stewardship, the Group has also added seven new business lines, diversified product ranges and entered new geographies.