This thesis concerns the work that has been done during graduation, conducted within Integrated Product Design of Industrial Design, at University of Technology Delft. It describes the design of a flexible Light Emitting Diode (LED) engine for Heritage luminaries, from Philips Lighting (Professional Luminaires). The light-engine should be applicable in 4 faces luminaires in France. LED it will reduce costs because of the significant reduction in energy use and price, while performance will be increased. LED engines are used for indoor lighting but also outdoor lighting. An LED engine is a light system that uses LEDs for illumination. Important issues are the heat management and glare. As the lifetime of the LED will be less if the heat sink is too small for the capacity required. Glare is a perception phenomenon what could appear with LED lighting. This blinding occurrence should be prevented with the final product. At first sight Heritage luminaires appear very similar. However, closer study shows a strong diversity concerning design, dimensions, ingress protection norms and the light system used. Reasons for this diversity include: differences in manufacturers, era of fabrication, production technologies and area of installation. Philips has knowledge concerning specific light systems for Heritage luminaries, and also has its own partners in the Heritage market. However, Philips does not have any Heritage luminaire models in its portfolio. Before starting to design the product, application specifications should be examined because a lot of variables can influence the criteria of the final design. A combination of light class, mast height, spacing, and road width has been set as the boundaries for the target application. The target countries of France, Spain, Germany and the UK are all affected by a number of sales related arguments: energy savings, ban on mercury lamps, Total Cost of Ownership, green image and maintenance. The levels of importance of these arguments can vary from country to country. In general, the municipalities will order the product on advice of installers. The product will be focused on the installers and citizens. The municipalities will be used as bases where the sales arguments can be applied. Eventually a list of requirements has been made to validate the choices for the final design. France is chosen as the main focus area because: 1. Overall similarities with all target countries 2. Amount of luminaires 3. HPL substitute After the analysis a brainstorm session has been carried out to obtain a sufficient morphological map. With this map a certain amount of ideas were generated. Eventually, 3 ideas were chosen to be developed at concept level. These were the ModuLED, the Chandelier and the Bowl. During meetings and e-mail communication with several employees of Philips Lighting the Bowl concept is chosen for the embodiment design. This choice has also been verified with the list of requirements. The Bowl will be interesting in differentiate aspects in relation to the current LED engine solutions. At the moment, LED engines have to be installed in local workshops. With the Bowl it is possible to install on site. Even the light positioning could be done on site, all of which results in a less expensive installation. Another distinguish feature is the flexibility. The flexible engine will give the municipality an option to choose what will be illuminated, thus preventing energy waste. In big cities in France, 25% of the luminaires are situated on the wall. The result with conventional units is a lot of light waste on these walls. With the bowl it is possible to avoid this aspect. The atmosphere lighting perception is also an important strength of the final design. Present LED engines provide directly aimed LED light via optics. The Bowl uses the remote phosphor layer technology which will provide homogenous light. The design uses 4 Fortimo TWIST modules which can be installed independently. This modular system gives the opportunity to vary with the lumen packages (1100, 2200, 3300 or 4400 lumens). The system will also be upgradeable with newer remote phosphor modules in the future. The concept has the potential to grow within Philips? remote phosphor platform. A demonstrator of the Bowl will show if the assumption concerning ambiance illumination is valid and if less glare will occur. The demonstrator resulted in several recommendations regarding light perception. The use of frosted protection caps will be needed in luminaires with clear glass because there was too much glare from the light. Eventually the illumination was well received by employees of Philips Lighting. In the end, a final design has been made. All features of the concept have been explored, new solutions have been generated and some of these have been introduced into the final product. Eventually, a 3D model is made with 3D design software. Most of the components have been calculated regarding the feasibility. Some components have been designed on the basis of suggestions from engineers within Philips Lighting and TU Delft, and others based on general assumptions. That is because more time was needed to calculate or analyze each component in depth. A number of tests have been done in respect of light distribution. An application area was identified via 3D light visualization software. Some features have to be verified. While the results are quite positive, with an improved reflector design the modules could provide much better light distribution. A spot on the ground could be more spread over the surface. Another improvement should be done by verifying the frame. Overall, the Bowl is a realistic design which is confirmed by the analysis and list of requirements. The final design is flexible in terms of lumen package and light positioning. It is suited for installation in “all” 4 faces in France, easy to upgrade, easy to install and the design also has a high IP rate.