Before a property can be attributed to an object, the object itself must be recognised, that is to say, distinguished from its surroundings. This process of interpretation has been used to formulate laws according to which certain arrangements are grouped together to form shapes, i.e. objects of perception. These laws of gestalt are of practical interest to the lighting designer. Every lighting installation comprises an arrangement of luminaires - on the ceiling, on the walls or in the space. This arrangement is not perceived in isolation, but in forms or groups in accordance with the laws of gestalt. The architectural surroundings and the lighting effects produced by the luminaires produce further patterns, which influence in our perception of the space.