The network won the account after a pitch run out of San Francisco against a number of international networks and a final shoot-out against Wieden & Kennedy.
Dave Higgins, the director of European marketing communications for Deloitte Consulting, said: "We believed the campaign ideas DDB presented were going to be a better way to break away from the sea of sameness and crushing dullness in the industry."
BMP DDB will act as the European creative hub, while DDB's San Francisco office will run the US portion of the business. Half the spend is likely to go to the US, while the other half will be shared by key markets including the UK, France, Germany, Australia and Hong Kong.
Media arrangements for the account have yet to emerge.
Ross Barr, the joint chief executive of BMP, said: "We are really excited to be launching a new advertiser and new brand into this emerging advertising area."
Deloitte's rivals have also begun separating their consultancy businesses from their branding arms in the aftermath of the Enron/Andersen scandal. In April, PricewaterhouseCoopers appointed McCann-Erickson to its £62m account and Cap Gemini Ernst & Young recently appointed StrawberryFrog to its international business.
Higgins said: "We would see that facility being provided and coming altogether from DDB. Ultimately the magic from an ad comes from its creative. The media buying is more of a commodity."
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