I think the binding is done the way that I did my 6 I Spy quilts. It is called "pillowcasing" the quilt. If I remember correctly, you layer the quilt with batting then the backing right side up, then the top right side down and sew all around the edges, leaving a 8-10" hole. Then you flip it inside out. Then you can quilt it and whip stitch the hole closed. Someone in my guild had suggested that I do my 6 quilts that way beacause I was running out of time to have them all done by Christmas. When I was done, I topstitched around the edges around 1/4" so that it has the illusion of having the same color binding. This is the first time I've seen it on another quilt!