G4S says it will appoint a chief operating officer to work closely with chief executive Nick Buckles on customer service and project delivery.
It has also promised to carry out more rigorous risk assessments of new contracts and will demand board-level oversight on contracts where annual revenues exceed £50 million.
G4S said its board had decided that it was in the best interests of the company and its shareholders that Buckles remains as chief executive.
Buckles, who admitted to MPs that the Games staffing episode had been a "humiliating shambles", was not guilty of any significant shortcomings in his performance, the company said.
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