The agency is charged with developing Amnesty's strategic positioning, in a move to revitalise its profile and help it reach more people.
The appointment comes after a six-week pitch, overseen by Kerry Hutchinson, marketing director for Amnesty International UK, where Amnesty worked with the agencies to define a strategy that would be at the heart of everything the organisation does.
According to Hutchinson: "It was a tough choice but Mother won through with work that was brave and made us feel uncomfortable -- and that's exactly what we wanted. We're delighted to have it be a part of the human rights movement."
Amnesty campaigns on a wide range of issues, including abolition of the death penalty, the rights of political prisoners, and arms control. It is looking to strengthen the presence of its brand at a time when it says its work has never been more urgent.
Stef Calcraft, a partner at Mother, said: "Amnesty is a very special organisation that has a natural fit with Mother. The last thing it needed was an advertising idea, which is why the brief itself was one of the most interesting we have worked with."
Amnesty does not have a retained agency, choosing to work with several different agencies on one-off projects, and its other relationships are not affected by Mother's appointment.
Karmarama, the communications design agency, was recently appointed to create a campaign as part of a drive to stop violence against women. Catalyst works with Amnesty on direct marketing.
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