The National Gallery of Art is home to one of the most highly respected and extensive art conservation laboratories in the world, with a staff of more than 50. Among them are not only conservators of paintings, three-dimensional objects, works on paper, photographs, textiles, and frames, but also scientists and specialists in preventative care, which encompasses everything from monitoring environmental conditions to pest management. In addition to treating works of art in the collection, conservators and scientists collaborate with curators to perform research that improves our understanding of artists’ techniques and materials, and ultimately of the works of art and their historical contexts. In this lecture held on July 16, 2017, Mervin Richard, chief of conservation at the National Gallery of Art, discusses the history of conservation at the Gallery and some of the many activities that occupy the department today.