Jennifer Creegan, general manager product marketing at Microsoft Advertising was speaking to Media Week at the Microsoft Imagine held in London's Tech City.
Creegan said that the new in-app ad products for its Windows 8 operating system would change the way marketers allocate budget.
She said: "Marketers will have the opportunity to look at where consumers are spending their time in the Windows 8 ecosystem and what part of their budget should be going towards it, rather than what part of its traditional or digital budget should be allocated.
"This will be an evolution over time, but I do think our offering is a unique digital amalgamation that can bring this all together."
Microsoft has enabled rich-media ad campaigns, which can include video and games, in apps on its new operating system, spanning mobile, tablet and PC.
The first tranche of advertisers rolled out their campaigns across Windows 8 last week, with Sky, Lloyds TSB and Vodafone among the first in the UK.
Microsoft faces tough competition in the online advertising market from Google, Facebook and Apple.
Creegan claimed that what gave Windows 8 an edge was "the potential of scale and its unique design element."
She said: "I don't think anyone else has the cross-screen value product that we have between Xbox, mobile and Windows tablet/PC ecosystem."
Microsoft hosted its annual event at Modern Jago in Shoreditch, which it is leasing until the new year, and is hosting a number of events for creatives and developers.
Speakers at the afternoon event included Andy Hart, general manager for Microsoft Advertising and Online UK; Dave Coplin, chief envisioning officer at Microsoft, and Gareth Dunsmore, marketing communications general manager at Nissan Europe.