Dahler held various correspondent and anchor positions at three major networks: ABC, CBS, and FOX.
On May 27, 2008, the Daily News reported that the station had decided to give Don the co-anchorage for the 12 noon and 6:00 p.m. newscasts, which paired him with veteran Dana Tyler; all of this just five days after two-time alum Jim Rosenfield was let go for the sake of budget cuts.
On September 8, 2011, it was announced that Dahler would move to weekends, as Chris Wragge was returning to the local station from a 9-month stint as co-host of CBS' The Early Show.
Since then, he has filed reports for all programs at ABC, including Nightline, Primetime, 20/20 Downtown, Good Morning America and World News Tonight.
On September 11, 2001, Dahler was the first network correspondent on the scene of the attack on the World Trade Center in New York city reporting live via telephone from his apartment—which was just blocks away from ground zero—a few moments after the first plane hit the towers.
[citation needed] Formerly married to NBC News' Sara James, Dahler currently resides in New Jersey with his wife Katie and their two children.