In the current study, lighting is being examined as an integral part of the architectural design, in commercial stores. In the ever-changing world of trade, lighting has a prominent place, as it is an important mean for businesses to achieve goals. These goals are related to the overall purpose of the business, which is the profit. Depending on where the consumer is located, he or she must feel, move and operate in a specific way. Activities carried out in such places should be made under visual comfort conditions for both users and staff. In these processes, merchandise lighting plays a very important role. Techniques, systems that can be used, as well as the currently available technology, are being investigated. A flexible and efficient lighting system offers many benefits to a business, from the overall image of the space to the energy consumption. An analysis is also being made on how energy savings can be achieved, not only through the lighting system, but also through design techniques. Anticipation, in the early stages of design, for lighting, heating, cooling and ventilation has multiple benefits for the overall energy performance of the building.In addition, reference is being made to the applicable legal provisions in the European Union and the US, on total energy efficiency and mandatory values for lighting levels and installed power, for specific space and use. Finally, in the context of the study, a research was carried out, using the University equipment, in eleven commercial stores in the city of Volos to determine the levels of lighting in areas where customers and staff are moving around, as well as the window display.