Clockwise from top left: Edgar Damalerio, Kurt Schork, Mohammed Abu and Veronika Cherkasova. They were all journalists. They were all murdered. No one has ever been brought to justice in any of these killings.

Imagine the unthinkable: Having to pay with your life for an article you wrote, a photo you took. Because it offended someone, because it touched a sensitive subject.

Imagine that the person who killed you - who shot you in the head, who stabbed you to death, who threw a bomb into your office - walks free for the rest of his life. While your family, your friends and your colleagues never get a chance to get on with their lives, having to live with the fact that your murderer was never caught. This is the reality for hundreds of journalists that have been killed over the last ten years.

Today the general public is becoming more aware of the risks journalists take while doing their job, and that it can sometimes be fatal to be a reporter or a cameraman. However, few are aware that the vast majority of crimes against journalists go unpunished.

For this reason, WAN has chosen impunity as the theme for this year’s World Press Freedom Day campaign. We want to raise awareness about the culture of impunity. We want to pressure governments about this issue. It has to stop.

We need your help in doing this. We are offering you a package of editorial and advertising materials, including interviews, essays, infographics, detailed cases of journalists killed and imprisoned in 2004, cartoons, photos and advertisements. We encourage you to participate in the campaign against impunity by using some or all of the materials in your publication on 3 May or the nearest day on which you publish.

To raise awareness. To stop the culture of impunity. To pressure governments. In the name of freedom of expression.