The Cheltenham-based charity specialist agency won the business after a three-way pitch. The win follows the agency's success in picking up international development charity Everychild earlier this month and the National Trust earlier this year.
For The Children's Society DMS will work on attracting as many as 10,000 donors by the end of the financial year, as part of the charity's Safe and Sound campaign.
Maxine Reynolds, senior account director at The Children's Society said: "DMS impressed us with its emotive creative concepts and strong grasp of The Children's Society brand. It's really exciting to return to donor recruitment and we're confident we've picked the right agency to achieve our targets."
The agency has developed two creative concepts, which will be tested head to head in July. This will be followed later in the year by a further mailing that will highlight the desperate experience that many children go through when running away from home.
The charity, a voluntary organisation of the Church of England, launched its Safe and Sound campaign with the aim of helping to help make England a safer place for young runaways.
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