Osteogenesis imperfecta is a group of rare inherited skeletal disorders characterised by a greatly increased risk of fragility fractures. The reduction in bone strength is due to defects in its material properties and mineralisation. Low trauma fractures typically start in infancy e.g. as a consequence of falling when learning to walk. Rarely mild osteogenesis imperfecta can present for the first time during adulthood. Diagnosis is primarily clinical, based on a history of multiple low trauma fractures during infancy and childhood, and other clinical features.