Polyethylene (PE) liners are frequently applied in corrosive water services. As part of the a progressive integrity management and the drive for lowest life cycle cost, the use of PE liners in Oman has been extended to wet hydrocarbon services for new flowlines and pipelines as well as for retrofits. After some teething problems, installation is straightforward and operating experiences are good. Liners prove to be an effective means for a fit and forget system to prevent and eliminate leaks in aging systems.