From here:

The 40th annual Worth Bingham Prize will be awarded to Dana Priest and Anne Hull of The Washington Post for their series, "The Other Walter Reed" and "Walter Reed and Beyond" which ran from February through December, 2007. The award will be presented in at NPF's 25th Annual Awards Dinner on February 28, 2008.

Hull and Priest spent four months visiting wounded veterans of the war in Iraq without the knowledge of officials at Walter Reed Army Medical Center, uncovering horrific stories of neglect, substandard conditions, and an uncaring bureaucracy. Following their investigation the hospital's commanding officer, the secretary of the Army and the surgeon general of the Army were ousted. Immediately after the first articles were published, the Army began cleaning up the facility. Their series led to an examination of veterans' care across the country.