ABC News correspondent Chris Wallace is joining Fox News as host of the network's Sunday morning public affairs show. Wallace, who takes over the show in mid-November, also will play a key role in Fox News' election coverage, according to the network. He replaces Tony Snow, who will host a syndicated program for Fox News Radio. During his tenure at ABC News, Wallace most recently served as the senior correspondent for Primetime Thursday, and was also a frequent substitute host for Nightline. Prior to joining ABC News, Wallace was a White House correspondent for NBC News.