In this exquisite painting, Vermeer has achieved beauty in many dimensions: Light, Color, Composition and Mood. There is symbolism in the painting if you care to find it, but it is not the heavy-handed shopping-list of familiar tokens that we expect from some of his contemporaries.
The light from the window is rendered in several ways. The cloudy sky is reflected in the window-glass. The ochre wall shows subtle radiosity effects; the blue of the sky can be seen reflected from it near the window. Following up edge of the woman's dress, the wall color changes from red-brown to blue-white, an effect that also accentuates the contour of her hip. The light on the starched, white headdress is very delicate, with blue, yellow, transparency, crinkles, folds, corners. There is a suggestion that as the blue of the sky is re-radiated from the headdress, so the woman's presence brings the sky into the room. The black and yellow dress is painted with bright highlights of paint and also hints of blue that give a subtle sheen to the material. The reflections on the pitcher and dish are also painted with exquisite care, with the red oriental rug on the table reproduced on the underside of the dish, and a more diffuse red stripe on the side of the pitcher.
Compositionally, the woman acts as a bridge from the window frame to the table, with a balance from the map at the top right. The eye moves easily between these three places on the canvas: window, woman, table, the curves of her figure integrating the rectangles. Note how the contour of the pitcher continues smoothly up the woman's sleeve. The negative spaces of the composition are the counterpoint; consider for a moment the three major wall-areas and how they balance the three areas of positive space. Perhaps in Vermeer we can see the precursor of that other Dutch master of composition, Piet Mondrian.
The woman's tranquil mood pervades the scene, quiet and pensive, but with the momentary action of opening the window to enliven the scene. On the table is a jewel box with the blue ribbons spilling out, and behind is a blue dress. She is perhaps doing her wifely duties, but thinking of the outside world -- the window and map -- and thinking of dressing up for a night on the town.