Considerable advances have been seen in materials with tailored nanostructures in recent years, owing, in part, to increased demands placed on material properties in fields, such as tissue regeneration and wound healing. This review focuses on the developments made in nanoporous bioactive glasses, their novel nanocomposites and their application to bone regeneration. Bioactive glasses have the ability to stimulate new bone growth as they dissolve in the body. Sol-gel bioactive glasses have a nanoporosity that provides sites for cell attachment and tailorable degradation rates. Importantly, the glasses can be made into interconnected porous structures that can be used as 3D templates for bone growth, although, because they are glasses, they cannot be implanted directly into sites that are under cyclic loading. Composites provide a partial solution to this problem, although their bioactive and degradation properties are not ideal, therefore novel nanocomposites are needed. The route to these potentially ideal materials is described.