In this series of four teacher workshops, Walters conservators, scientists, and educators explore the many connections between science and art. This session will introduce participants to the chemistry and physics of pigments or colorants. Selected pigments will be illustrated with examples from the Walters’ collection, providing context for their use in the history of art. Pigments will be used as a point of departure to discuss oxidation and reduction reactions, acid-base chemistry, and the effect of optics on the perception of color.