Abstract: An inexpensive mailing envelope with a window opening to which a decorative image-bearing sheet member is attached. The image-bearing sheet member may be transparent or semi-opaque, partially revealing the contents of the said envelope. The inclusion of a decorative image visible from the outside of the envelope induces mailing recipients to open the envelope and examine the contents inserted therein. The window opening may be placed on the rear panel of the envelope, opposite the panel displaying address information. The image-bearing sheet material may be detachable and may be promoted as a gift.