Don was born into an Irish-Hungarian heritage.He has a sister (Gloria),and a brother (Dick Yarmy).Don served in the U.S. Marines in World War II, and contracted malaria during the Guadalcanal campaign.He married singer Adelaide Adams and adopted her stage surname.He has seven children named: Carolyn, Christine, Catherine, Cecily Adams, Stacey Adams, Sean, Beige.Don was married three times.

The series also gave him an opportunity to direct. In 1971, Adams moved onto another genre-spoof TV series, The Partners, in which he played police detective Lennie Crook. but the series was poorly received by the public and perished after thirteen weeks. After this debacle, Adams found the going rough for a while, though he made a comfortable living with nightclub appearances and guest spots on such TV series as The Love Boat. He made no fewer than three attempts to revive Get Smart between 1980 and 1994, one of which actually resulted in a (very short-lived) weekly Fox network sitcom. Adams is best known to children of the 1980s as the voice of cartoondom's bionic blockhead, Inspector Gadget.