In one form or another, public service announcements (or advertisements) have been with us for well over a hundred years. They have as their chief objective the goal of educating the general public in order to raise awareness on a multitude of social issues; from cancer and global warming to domestic violence and drug abuse. PSAs seek to cause action and change opinion.

It's little wonder, then, that to capture society's attention in an age of visual inundation, the creators of public service campaigns have had to step up. The likes of such major ad players as Ogilvy, Grey, and McCann-Erickson — along with the creative minds of boutique agencies — have risen to the occasion, producing a new generation of printed public interest ads. Some are edgy and envelope-pushing, using imagery that makes the viewer uneasy. Others go for power through simplicity, employing striking illustrations to move an audience.

One thing that all of these ads have in common is their striking visual impact: Photoshop work isn't just effective, it's epic; illustrations aren't just employed, they're integral.

Below is a collection of 25 standout public interest ads whose creativity, art direction, and emotion-evoking properties work together to deliver a poignant message. They are a good reminder that delicate subject matter is oftentimes most successfully delivered when the inclination for gentleness is abandoned and instead is confronted head on. These are ads that make a statement...quite literally.

WWF: Tree

Heart and Stroke Foundation: Future

Salvation Army: Politician

Surfrider Foundation: Plastic Invasion

World for All: Train

Dutch Heart Foundation: QR Bystanders

Amnesty International: Tsunami

Ecuadorian Red Cross: Life Inside Life

Department of State Health Services: Share Air

World for All: Building

WWF Desertification: Elephant

Amnesty International: Pencil

Operation Smile: Charlie Dot

Safe Kids: Football

OndAzul NGO: Sardine

Operation Smile: Sally Monkey

TAC: Confusion, Overpass

Samusocial: Stop the Nightmare

Fight for Peace: Favela

Canadian Journalists for Free Expression: Tara

Pedestrian Council of Australia: Man

Stivoro: Open Road

GirlHub: Amina

Global Warming

Utah Department of Highway Safety: Alcohol Cuffs

Greenpeace: Become David

So Acao Solidarity Movement: Much More than Trees

Which ads resonated most with you? What tactics do you think work best in public service ads? Let us know in the comments.