Maria Hill
Commander Maria Hill is a fictional character that appears in the universe of Marvel Comics, and is a supporting character in most of the Iron Man comics. Hill is an agent (and later director) of S.H.I.E.L.D. She is also an ally of Nick Fury and the Avengers, mainly it's prominent members, Iron Man and Captain America.
She was created by Brian Michael Bendis and David Finch, and first appeared in New Avengers #4.
In the Marvel Cinematic Universe, Maria is played by Cobie Smulders, who also played Robin Scherbatsky in How I Met Your Mother.