A sign comprising a surface having a display, and a plurality of sources of visible light. The sources of visible light are oriented to illuminate at least a portion of the display, and include solid state light emitters and/or luminescent materials. Line segments drawn on a Chromaticity Diagram connecting coordinates of some of the illumination color hues define a shape which encompasses coordinates of the display color hue(s). Also, a sign comprising a surface having a display having a surface area of at least 4 square meters, and at least 100 sources of visible light including solid state light emitters and/or luminescent materials. Also, a sign comprising a white light source and at least one additional source of light. Also, methods of illuminating signs.