13. Avanade

Revenue: £326.8m (+48%)

Staff: N/A

The UK arm of the Accenture/Microsoft joint venture inched up two spots in the list this year, breaking the top 15 with 38.6 per cent revenue growth.

The Fenchurch-based UK arm of this global business is highly focused on innovation, and benefits from multiple research and innovation projects within the Accenture group.

The focus on challengers culminated in Avanade's buyout of Quantiq Group for £63.2m last year.

This is also the ethos espoused by the MSP's chief innovation and sustainability officer, Annette Giardina, in a recent interview with CRN.

Giardina detailed how the company has always had a robust Microsoft-focused strategy, but over the past couple years this has evolved: "We now partner with any company in the Microsoft ecosystem, not just Microsoft. This includes start-ups and challengers."

She explains Avanade started its ventures business a few years ago to focus on partnering with start-ups and challengers, rather than only large vendors.

"We have a structured process for researching and selecting partners that reinforce our priorities around diversity, inclusivity, sustainability, and responsible business practices.

"By working with start-ups, we bring external innovation into our business and to our customers."