"Robin and George are the right pair to lead our effort. As we've seen over time, Robin brings a warmth and intelligence to the morning that no one can match. Hers is a practical curiosity that brings the viewers' questions to the fore. George complements Robin's strengths with a deep knowledge of and commitment to news about the nation and the world. George is a formidable interviewer who brings the viewer a deeper understanding of the great issues of the day through his conversations with experts and newsmakers," said ABC News President David Westin in a statement.
"Sam Champion brings his knowledge and enthusiasm to weather, climate, and the environment. Juju, our new news anchor, has distinguished herself covering the news of every sort - from national and world events to the everyday experiences of parents and families," he added.
Stephanopoulos, 48, has been ABC News' chief Washington correspondent since December 2005 and host of ABC's Sunday morning political affairs program, "This Week With George Stephanopoulos," since September 2002. He will take on the role of chief political correspondent and continue to anchor "This Week" until a replacement is named, Westin said.
Chris Cuomo will be promoted to co-anchor of 20/20 with Elizabeth Vargas and serve as ABC News' Chief Law and Justice Correspondent.
Diane Sawyer, who's last day on GMA is Friday, will be taking over as anchor of World News on December 21, succeeding Charlie Gibson.
"One cannot describe all that she has done for GMA; nor can we fully express our gratitude. The best way to honor what Diane has done - and what Charlie did before and with her - is to continue the great tradition while building on the foundation they have laid. This new team will do just that," Westin said.