Research In Motion is to cut about 2,000 jobs, representing 11% of the Blackberry-phone maker’s workforce.
The Canadian firm also said its chief operating officer Don Morrison is planning to retire and Thorsten Heins is taking on the expanded role of COO, product and sales.
The news comes after RIM announced in June that it had missed its lowered profit forecasts and reduced its predictions for the full year.
The company’s share price has fallen by more than 50% since the start of the year.
RIM made a net profit of $695m (£430m) in the three months to 28 May, down from $769m in the same period last year.
It had warned in April that its profits would be low because of reduced shipments of its Blackberry phones.
Blackberry has been overtaken in the smartphone market by sales of phones running Apple and Google Android operating systems.
In a statement, RIM said it needed to make the changes in order to “focus on areas that offer the highest growth opportunities”.
RIM has already announced a cost-cutting programme, which includes job cuts, but had not given full details.
As well as cutting costs the company hopes the changes will increase the speed at which it can bring products to market.
The smartphone manufacturer has not yet announced any one-off expenses as a result of the programme – such as redundancy payments.