Sandwich construction has been used for many years in aircraft and missiles, because of its ability to provide strong, stiff, lightweight structures. While the technology is well-developed for certain combinations of materials, there are many new developments which will have a significant impact on future applications. These new developments can be grouped into the following categories: 1. Joining methods. 2. Materials. 3. Geometries. This paper describes new technologies being developed in each of these categories and the impact they will have on sandwich construction.