A Palladian shelf is a shelf, typically made of wood that goes above the blind/shade and allows you to do a ceiling mount for the shade. It can come is all different colors and stains, so you can match to the existing window trim color and make it look like it is part of the window. Typically arch windows won't have anything between the arch and the rectangular area. On a wide window, you would need to have a bracket in the center, the palladium shelf allows for this.
