The agency is in the process of creating a campaign that will include direct mail, viral email, TV and cinema for the charity, which fights poverty in developing countries. Event materials for festivals will also be created, such as posters and stickers, and also bottles of water that will include a message for consumers to send in the bottle to Chancellor Gordon Brown.
The creative idea shows a fat cat businessman urinating into a glass of water -- the glass is then passed onto a poor African boy to drink.
Steve Tibbett, head of policy and campaigns at War on Want, said: "We came to Joshua because we heard that it was producing some edgy work which we wanted. It has impressed us by grasping a difficult and complex problem and communicating it in a clear unambiguous, arresting manner."
The campaign seeks to draw attention to the pressure that third world governments are put under to privatise public services, such as water, electricity, education and healthcare, otherwise they face the withdrawal of much-needed aid. This often results in poor-quality services that the poorest people can not afford, leaving many without access to basic and vital resources.
Mitch Levy, executive creative director at Joshua, said: "This emotive and relatively unknown issue has given us the opportunity to create an outstandingly effective integrated campaign that sweats every penny of the budget."
The integrated work breaks on April 19. The win follows that of the £3m Cobra Beer account, which Joshua picked up last week.
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