Fluoroscopically guided interventional procedures require adequate image quality for medical decision making and eye-hand coordination. Other activities requiring light must be performed while the operator views the images. The lighting environment of a typical modern interventional cardiology laboratory was photographically documented during the performance of several interventional cardiology procedures. This laboratory was originally constructed in 1990, and reequipped several times. No one focused substantial attention on lighting design at any time. Key elements of the room design were simulated using a commercial 3-D rendering program. Matching photographs of the actual room with the simulation provides a semi-quantitative estimate of the properties of the real room and its equipment. The clinical images on the viewing monitors are overlaid by a substantial degree of diffuse reflections as well as a number of direct and indirect specular reflections from other light sources in the laboratory. Their intensity was greater on those monitors that incorporated a glass protective plate in front of the LCD displays. The effect of reflections on performance is quantitatively unknown. Extinguishing offending lights cannot be done without interfering with other critical aspects of the procedure. However, simple changes in room architecture and equipment should substantially reduce reflections.