Plein air painting is landscape painting in the "open air." While the act of painting outdoors was hardly new, it was not until the advent of the Impressionists that moving out of the studio and painting en plein air became an accepted style of landscape painting. Plein air painting is characterized by less detail and the plein air painters' desire to capture the fleeting moment. Plein air landscape painters believe they are much better able to convey the light and atmosphere outdoors than traditional landscape painters can in the studio. An important corollary development was the new form of packaging of paints in tubes, making it possible to easily transport paints to wherever the plein air artist chose.
Contemporary plein air painting continues to be very popular, particularly in the United States. Associations, typically located in coastal regions and the southwest, organize Paint Outs or other excursions where artists get together and travel to a location to paint en plein air. This tends to make plein air painting one of the more social art forms. Given the need to work quickly and without repeated passes of the brush, plein air landscapes are typically spontaneous, fresh and bold in feeling and look.