In gum bichromate printing the paper is coated with gum arabic which carries a pigment, and is sensitized with a bichromate. On exposure to UV light the bichromate causes the exposed gum arabic to harden and become insoluble in proportion to its exposure. The areas not exposed to light remain soluble.

The print is developed by floating it face down in water. The unexposed portions dissolve taking the pigment along. The insoluble portions remain on the paper. The print can be manipulated while developing, allowing the printer to make many local modifications. Any watercolor pigment can be used allowing the printer to choose the color of print. It is also possible, though very challenging to make full color prints using multiple printing with different colored pigments and color separation negatives.

In order to get a good print it usually necessary to multiple print, that is to coat, expose and develop the same print repeatedly to develop a full tonal scale. This requires some sort of registration technique.

Gum bichromate printing can be very demanding because of its flexibility. The final gum bichromate image is usually somewhat soft.