Solid state lighting is a fascinating research field which brought up the revolutionary breakthrough technology of inorganic LEDs during the last decade. These are now migrating into the general lighting field. A new development route is already identified with organic light emitting devices in large area and nm-thin architectures being complementary to inorganic point sources.These organic light-emitting devices (OLEDs) for lighting purposes are expected to have broad market opportunities due to their out-standing properties. They can act as nearly two dimensional diffuse light sources as well as for signage applications. They have the potential to offer transparency and flexibility paving the way for completely new applications. As efficiencies above 50 lm/W are targeted these novel light sources have also the potential to decrease the global energy consumption.Similar efficiencies and lifetime compared to existing solutions is a prerequisite for new lighting technologies. A staircase improvement from today's level towards 50 lm/W and 5000 h lifetime of large area tiles can be expected which will be sufficient for first niche applications soon.However, an effective market introduction of OLEDs for lighting and signage would become the lighting revolution in the future as soon as:•\tthe cost structure is competitive•\ta unique selling point like transparency is explored.So one of the major "road block" that is still ahead are manufacturing costs: If no breakthroughs in terms of new low-cost processes are made, OLED technology will not enter the market in large volume, even if the performance would allow competing.The second issue to be addressed in CombOLED takes care about the uniqueness of OLED for lighting: Besides the advanced form factor of OLED lighting panels further unique selling attributes must be develop. Within CombOLED the emphasis is on creating transparent devices which will open a completely new perspectives for lighting and signage.