We report on high-vacuum nanoimprint lithography onto chromophore dye molecules embedded in optically inert polymer matrices. A specifically designed high-vacuum (10(-5)-10(-6) mbar) chamber to perform nanoimprint lithography at temperatures up to 300 degreesC and pressures up to 10(5) psi on areas of more than 25 cm 2 allows us to imprint in principle any class of thermoplastic molecules without loss of functionality. We tested our system by imprinting different polymers and polymer/dyes blends, demonstrating that the photoluminescence efficiency of light-emitting molecules is preserved in the lithography process. (C) 2004 American Vacuum Society.