Un-Reinforced Masonry (URM) buildings are popular all over the world including Sri Lanka because of their durability, low cost, construction easiness and architectural character, need of less skilled labour, eco-friendliness and use of locally available materials such as ashlar or rubble, adobe and brick. However, these buildings have a higher probability of failing under natural disasters such as earthquakes, tsunamis and storm surges, floods, cyclones and landslides. In Sri Lanka, winds, landslides and floods have frequently occurred. In addition, a massive tsunami adversely affected the people in 2004 and its effects to islands on the Indian Ocean have been continued since December, 2004. Minor earthquakes have come off recently with experiences of wall cracks and no deaths. It is also believed that, there is a defused plate boundary in the making some 500 km south of the southern tip of Sri Lanka which might be the cause of these tremors or minor quakes. Further, an earthquake occurred in Colombo area in 1615, has caused around 2000 of human deaths. Therefore investigation of performance of URM buildings against these natural disasters and possible retrofitting methods are increasingly important. In this review study, an attempt is made to identify the performance of URM buildings against natural disasters and identify retrofitting methods that can be applied to existing building, to enhance the strength proper ties of structural components. Common failure mechanisms for URM structures consist of separation of walls at corners, diagonal cracking or vertical cracking in walls, separation of roofing from walls, out-of-plane wall failure, in-plane wall failure, shear cracks and de-lamination. These damages on a wall diminish the service life of building. In addition, different kinds of retrofitting methods: ferrocement, poly propylene mesh and bamboo reinforcement, for URM structures to be seismic resistant are presented. Mechanisms of failure of URM walls and effects of retrofitting techniques to reduce the damage are also discussed. ENGINEER, Vol. 47, No. 03, pp. 71-82, 2014