In the second half of the twentieth century scientists discovered that light travelling through bended glass rods could be used to transmit data. It took a few more decades for the technology to mature but since the beginning of the 21st century data transmission through fiber optic cable has become a technology without which our modern world as we know it would not be possible. But the potential of fiber optics has evolved even further and is currently revolutionising the world’s pipeline industry. Although already around for a couple of years, in a necessarily conservative industry that is a very short time span. But nowadays even giant operators like Saudi Aramco show an increased interest and effort in adopting the new technology, complementing or even replacing existing traditional monitoring systems. Monitoring pipelines with fiber optics offers three specific applications which allow pipeline operators to enhance the integrity of their pipelines and thereby save cost for repair and down-time: • Protection against Third Party Intrusion • Detection of Spontaneous Leaks • Tracking of Pipeline Inspection Gauges The basic principles of these three applications will be illuminated as well as some of the practical challenges that have to be overcome to optimise system performance. Finally, three brief case studies will be presented highlighting the benefits which pipeline operators could harvest after implementing a fiber optic based pipeline monitoring system.