54. Itelligence

With revenues approaching €900m and 7,000 employees, Germany-based Itelligence is one of SAP's largest partners globally. Its UK arm hit £65.7m revenues in its year to 31 December 2017, a 10 per cent rise. UK net profits inched up from £3.9m to £4.2m. Offering a range of services including consulting, managed services and training, NTT Data-owned Itelligence claims it leads the way in new SAP technologies, including S/4HANA digital core.