Yahoo is overhauling the way it sells advertising in the US in an effort to help revive the business.
The internet firm, whose boss Terry Semel quit this month after recent poor trading, is merging its display and web search advertising operations.
The firm"s most senior US advertising executive has also left the business.
Hugely reliant on advertising for its revenues, Yahoo said the shake-up would better position it to sell ads across different formats.