Managed service provider Arkphire has secured a seven-year contract with The London Clinic worth £50m.
The deal will see the Irish firm deliver outsourced services in "all aspects of IT". The two firms have already been working together over the last five years.
Jimmy Dalton, CFO at Arkphire, said: "We are delighted to continue our long-standing partnership with The London Clinic and to be enabling their business transformation efforts.
"We are very proud to be delivering core services to a front line provider of outstanding healthcare."
The London Clinic is a private hospital operating across seven sites around the Harley Street area.
It claims this new partnership will enable it to innovate its digital capabilities, calling it "a game changer".
James Maunder, CIO at The London Clinic, said: "The decision to progress with outsourcing core IT infrastructure services to Arkphire UK came down to trust.
"Arkphire has demonstrated real technical capability and a depth of insight about The London Clinic that gives us the belief that they're the best people to support our ambitious digital transformation plans.
"I'm confident in Arkphire's ability to innovate the service and to work in partnership with The London Clinic's Information Technology team in delivering the strategic needs of the business."
Arkphire claimed to have created a €150m-revenue MSP powerhouse when it completed the acquisition of Trilogy earlier this year.
Neither of the two now-merged businesses disclose their revenue in the UK with Companies House.
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