Silk is compared with wool relative to its dyeing properties, demonstrating a slightly lower substantivity, better intrinsic leveling, and lower combining power. Sericin is the gum which binds the fibroin filaments in the fiber, and, prior to dyeing, is removed by degumming. Weighting and bleaching are optional processes. Specialized processes and machinery used in dyeing silk and silk blends are also described. -- AATA