NLR developed a Runway Incursions Alerting System (RIAS) for all runways of Amsterdam Airport Schiphol to enhance airport safety. The system is indicating violations of an area around the runway that protects aircraft that are about to land or take-off. To come to the end result the concept development, prototyping and validation was all done on NARSIM Tower. Subsequently NARSIM tower was used as platform for integrated system testing before the final system was installed at Schiphol. The RIAS system works under all visual conditions and includes audio and visual alerting and was used by Dutch ATC LVNL. Visual alerts are shown to the air traffic controller using bubbles as part of the Advanced-Surface Movement Guidance and Control System (A-SMGCS) system. Alerts also appeared in the Radar screen of the approach controller.