Historic decoration is often buried under many layers of paint and/or plaster. Paint analysis provides an excellent quantitative understanding of the paint layers and media composition, but limited in understanding the full scope of decorative campaigns. To gain necessary details of pattern, design composition, tools and techniques used, it is often necessary to see it. Exposure windows are made by delayer the paint by either mechanical or chemical methods to reveal the target layers. The information gathered is vital when recreating historic decoration or simply confirming what is found in the analysis. When found intact, original decoration of entire rooms can to revealed and conserved.