Dana Welles Delany was born on March 13, 1956 in New York City to parents of Irish descent and was raised Catholic in Stamford, CT. Dana knew at an early age she wanted to be an actress. She attended Phillips Academy in Andover, Massachusetts for her senior year, and was a member of the school's first co-educational class. She attended Wesleyan University and graduated in 1978 and moved back to New York and developed her skills working in daytime television and theater. Dana starred in the Broadway show A Life, and received critical acclaim in a number of off-Broadway productions. Dana acted in a number of TV series after moving to Hollywood including guest spots on "Moonlighting" and "Magnum, P.I". She worked steadily until she would, in 1988, get her own staring vehicle – ABC TV's critically-acclaimed series China Beach in which she played Army nurse Colleen McMurphy. This role earned her 3 Emmy nominations and 2 Emmy Awards as Best Actress. Dana moved onto starring roles in movies Such as Exit to Eden (1994). She portrayed Andrea Beaumont in the 1993 animated feature film Batman: Mask of the Phantasm based on the popular TV show Batman: The Animated Series. She was later cast as Lois Lane in Superman: The Animated Series. She reprised her role as Lois Lane for Justice League, Justice League Unlimited, and The Batman. She appeared in Pasadena and had multiple guest appearances on shows like Law & Order: Special Victims Unit, Boston Legal, Kojak, Related, The L Word, and Battlestar Galactica. She joined Desperate Housewives in the 2007-2008 season as Katherine Mayfair. She also appeared as FBI agent Jordan Shaw in a two-part story on the series Castle.
Delany left Desperate Housewives to star in the new ABC series Body of Proof in Spring 2011.
Dana serves on the board of the Scleroderma Research Foundation and is a board member of the arts advocacy organization Creative Coalition. She has never been married but has said that after turning 50, she is definitely ready for a man in her life.