Susan Michaela Sullivan (born November 18, 1942) is an American actress. Sullivan is best known for her roles as Lenore Curtin Delaney on the NBC daytime soap opera Another World (1971–76), as Lois Adams on the ABC sitcom It's a Living (1980–81), as Maggie Gioberti Channing on the CBS primetime soap opera Falcon Crest (1981–89), as Kitty Montgomery on the ABC sitcom Dharma & Greg (1997–2002), and as Martha Rodgers on Castle (2009–2016). She earned an Emmy nomination for Lead Actress for the role of Julie Farr in Julie Farr, M.D. and a Golden Globe nomination for Supporting Actress as Montgomery.