Fiber-optic sensors that are imbedded within composite materials could provide structural information during the life of the component, thereby avoiding many of the mechanical failures that today result in death, injury, or environmental accidents. Eventually this fiber-optic smart structure technology could lead to radical new thinking in terms of engineering and structural integrity monitoring. An overview of this progress will be given, which will include the development and characterization of a number of fiber-optic strain sensors including a fiber-optic strain rosette for mapping two-dimensional strain fields within composite materials, the detection of stress-induced acoustic emission, and the development and testing of a multilayered fiber-optic damage detection system fabricated within a full-scale composite aircraft leading edge.