Grisaille (Fr. gris, grey) is a term for painting executed entirely in monochrome, in various shades of grey, particularly used in decoration to represent objects in relief.

A grisaille could not only be executed for its own sake as a decoration, it may also be the first stage in building up an oil painting, or it could be used as a model for an engraver to work from.

For example, the ceiling frescoes of the Sistine chapel have portions of the design in grisaille. At Hampton Court the lower part of the decoration of the great staircase by Antonio Verrio is in grisaille.

The term is also applied to monochrome painting in enamels, and also to stained glass; a fine example of grisaille glass is in the window known as the Five Sisters , at the end of the north transept in York cathedral .