Alyson Hannigan (born March 24, 1974) is a Jewish-American actress known for playing Willow Rosenberg in Buffy the Vampire Slayer and its spin-off Angel and also for portraying Lily Aldrin on the CBS television sitcom How I Met Your Mother from 2005 to 2014.

For Disney, she voiced Winter in the Sofia the First episode "Winter's Gift", and appeared in The Torkelsons episodes "The Dance" and "Hot Ticket" as Samantha. She will voice Claire Clancy in Fancy Nancy.