Advertising about bad things is a tricky area. It is easy to associate the sender with the bad thing (Amnesty - rape) or at least just want to shut it out. I saw a really good one from the Red Cross though where they had managed to turn it into something positive.

(Big text) We want to see less of this
(Little image)

If you studied the image it was about something horrible like an hospital lacking medicines. The image text though informed you that although lots of hospitals in the world lacks medicines this picture was taken just before the Red Cross delivery reached this particular hospital.

Then as a follow-up they ran

(Big text) We want to see more of this
(Big picture) Help arriving at some godforsaken catastrophe

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