Charlie Gibson has announced that he will be stepping down as anchor of ABC's World News at the end of the year.
Diane Sawyer will be assuming the anchor position of World News in January 2010.
Sawyer's elevation means that, with Katie Couric, two of the three leading anchors for the broadcast networks will be women.
Gibson said he had been planning to retire at the end of 2007 but events compelled him to stay. He was named anchor following the death of Peter Jennings and the wartime injury of Bob Woodruff.
Gibson has been at ABC News for 35 years and says he plans to continue as an occasional contributor.
Gibson took over the ratings lead shortly after he took over at "World News." But he was eventually passed by NBC's Brian Williams, who has led in the ratings for nearly a year.