Abstract: A sun tie for attachment to a conventional vertical blind, when the blind is drawn to the closed position with the slats rotated to the position in which they are parallel to the plane of the window, to block entry of some heat and light, while permitting a view through the window. The sun tie has an anchor clip or pocket within which a left or right most one of a group of slats of the vertical blind is securedly retained. A group clip of the sun tie removably retains the remaining ones of the group of slats. Each of the sun ties preferably retains 4-7 slats, so that several sun ties may be required to be installed on a particular vertical blind, depending on its width.