Cable & Wireless Worldwide chief executive Jim Marsh has resigned, following the telecoms and networking company's third profit warning in less than a year.
He will be replaced immediately by the company's chairman, John Pluthero, who had previously also been a chief executive there.
However, the company has been heavily criticised by investors over executive remuneration, including for Pluthero, who will receive a £675,000 salary.
"Clearly it has been a very difficult 12 months and it is now important that we take the necessary steps to ensure the future growth of our business," said Pluthero.
Pluthero promised to radically improve the company's fortunes in several areas of techonlogy.
"I'll be looking to take a more radical approach to building on our hosting, cloud and data services business whilst becoming more competitive and efficient in the mature product areas. It has been easy to lose sight of what this business could be; it is my intention to reassert and realise that future."