Artists have long drawn landscapes with pencil, pen and ink, or chalk while sitting outdoors. However, the practice of painting in the open air-a convention popularized by nineteenth-century Impressionists- emerged in Europe only in the mid-1700s. Usually small enough to fit inside an artist's painting box, open-air oil sketches (often on paper, mounted on cardboard) were not intended for exhibition or sale, nor where they preliminary studies for larger, more finished pictures. Instead, these rapidly painted works remained in the studio as explorations of the immediacy of nature and the mutability of light, atmosphere, and climate. The sketches here-painted in the Italian and French countryside-demonstrate the sophistication and charm of the genre with their varying degrees of finish, structure, and point of view.