A noteworthy collection of drawings (ca. 1885-1930) produced by Louis Comfort Tiffany (1848-1933) and his studio artists sustained significant mold damage prior to its 1967 acquisition by the Metropolitan Museum of Art. In order to be exhibited and studied safely, the works required conservation intervention. Research was directed toward the identification of fungal contaminants to assess long-term health concerns and to determine the causes of dark fungal staining. Dematiaceous molds and fungal by-products were sampled from the works, which were water damaged sometime between 1933 and 1967. Scientific investigations included the use of classical and molecular techniques to identify the fungi, and the testing of oxido-reductases derived from the white-rot fungi Phanerochaete chrysosporium to reduce dark fungal staining on paper.