BT and consultancy firm Accenture have signed a 10-year, £306m business process outsourcing contract for HR administration services.
The deal is one of the largest HR contract renewals in the world, according to the companies.
The agreement, which starts in August, greatly expands the geographic reach of services that Accenture has provided to BT under an earlier, five-year contract.
BT said the programme was designed to give it higher levels of workforce management and performance services in 38 countries, and will deliver further cost savings.
Services to be provided include customer contact, recruitment, pension administration, payroll and benefits administration, performance management administration, health and safety, and HR advisory and information services.
The services will continue to be delivered through Accenture HR Services, which currently provides HR services to BT's 87,000 employees and 180,000 pensioners in the UK.
Under the new contract, Accenture will add services to another 10,000 BT employees in 37 countries.
Alex Wilson, BT group HR director, said, "This agreement will allow our staff to concentrate even more on the strategic role of HR management to our growing global business."