The agency will support the charity's fundraising strategy and look to increase income and awareness.
The first work by voluntary sector direct marketing specialist DMS will be a direct mail campaign to supporters in June. This will focus on helping children affected by HIV and Aids.
This mailing will be followed by a second trying to improve legacy giving to the charity, although this mailing is still in the planning stage.
Nick Marsh, Everychild supporter development manager, said: "It's harder than ever to stand out among so many other charities. This is an exciting time for Everychild and the appointment of DMS is part of our more high-profile fundraising strategy, but we are confident we are going to grow our donor base and enlarge our income stream."
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