Architecture and lighting have a dynamic relationship.

Although architecture certainly predates the modern concept of lighting, the application of these two quasi-sciences are now distinctly intertwined. The field is actually formally defined as a part of the greater practice of architecture. In its simplest definition, architectural lighting design is the arrangement of a structure's lights in a manner that compliments the building itself. This applies to almost every building imaginable, from homes to skyscrapers. Professionally speaking, lighting design as applied to architecture is concerned with three basic aspects of illuminating structures, aesthetic appeal, ergonomics and energy efficiency. Designers arrange lighting patterns and angles as to maximize or minimize these three main concerns. Much like architecture, lighting design isn't a true science or art, but rests in a grey area somewhere in between. The aesthetic appeal of a structure is something people generally have a difficult time qualifying. Like almost everything else in this world, some people like certain styles and others hate them. There are very few structures which strike people from diverse backgrounds as attractive or appealing. Taking that into consideration, think of the difficulty of a lighting designer's job. Not only must the architect take the total design of the building into consideration, but they have to arrange lighting which preserves the same visual appeal of the building using light and shadow at night. This proves to be a rather difficult proposition. In some cases, lighting designers take the opposite approach. Instead of matching the daytime visual style of a structure, they use the darkness of night to create a new style altogether. Making use of the darkness of night, light designers often will make use of shadows and carefully arranged lights to create a sort of optical illusion. As result, a given structure would appear to be dramatically at night than during the day. Ergonomics when applied to outdoor lighting, is a matter of practicality. Ensuring that lighting achieves its desired visual appeal is difficult enough as is. Arranging the pattern and luminosity of the lights so that they don't disturb onlookers or people inside the structure is even more difficult. The simplest approach is to avoid shinning lights directly into windows. With modern buildings that's easier said than done. Modern buildings make extensive use of windows, due to the availability and affordability of glass. Angling lights at ground level, or toward the buildings edges can achieve the desired effect without becoming a nuisance. Using lights that also minimize light pollution are a good tactic to reduce unwanted eternal light from inside the home. Energy efficiency is a worry everywhere lately. Commercial buildings have been concerned with reducing energy consumption by lighting much longer than residences, but the recent increase in energy prices has begun to change that. Making use of Energy Star, an industry standard to minimize electricity consumption, is an easy way to address this issue. Designing outdoor lighting for the home isn't something that a homeowner has to have done by a professional. Although it should be noted that its a good idea for some people. Light fixture companies regularly design custom fixture arrangements for the convenience of homeowners, or for home owners that aren't confident in making the right choice.