The charity has appointed the AAR to conduct the search. The process is still in the early stages; the company has only just started contacting agencies.
The brief is expected to handle the charity's digital communications, strategy and implementation.
Christian Aid does not currently have a retained digital agency. It has previously worked with a number of agencies for different projects. Agency.com rebuilt its corporate website earlier this year, and Poke created the online communications for Christian Aid Week in May.
The last work Poke created was online activity, which encouraged web users to make a single donation or commit to giving on a regular basis to the charity.
The ads adopted the line: "You add, we multiply," and asked people to donate everyday materials in favour of responding to disasters. The agency created an animation called "the multiplier" to dramatise the ads.
The line, which was introduced the previous year, was based on the saying: "Give a man a fish and feed him for a day, teach a man to fish and feed him for a lifetime."
Shop, previously called CDD, handled the direct marketing and advertising for the task.
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