The campaign will include banners and pop-ups across high-traffic UK websites including Handbag, eBay and Sky. It will run as a test for three months, with the aim of signing up new supporters paying via direct debit.
The campaign highlights 's work on the HIV/Aids crisis, a disease that orphans a child every 14 seconds.
Two creative routes are being tested. One is a straightforward message showing the emotional needs of children and the urgency required for action.
The second creative aims to get around the problem of donor fatigue. It focuses on two specific Save The Children programmes that allow children to raise pigs or plant tea, which provides the money for them to get an education.
Both banners click through to a landing page giving more information about Save The Children, along with an online donation page.
Richard Barron, marketing manager at Save The Children, said: "These are exciting times for us at Save The Children. Online is a channel that we are keen to explore and we are looking forward to seeing the results of some innovative creative work from Proximity."
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