Clean outlines give a clear indication of the borders of the subjects/shapes, setting each one apart from the others. Such outlines might serve as graphic elements that introduce a subtle abstraction, keeping a real or imagined scene from being perceived as fully immersive.

Clean outlines within a single piece might each have different widths, but each outline does not vary much in width from start to finish. The careful rendering of the outlines serves more as a graphic element and less as an indication of the artist's emotional state (as seen in works with undulating outlines.)

The outline is usually of a color and/or value that is distinct from the subjects/shapes. The color(s) chosen for the outlines might have a symbolic meaning, and varied colors can be used around different subjects to allude to a distinct aura that each subject has.

Featured: Rêverie by Alphonse Mucha.