The author proposes an interpretation of the dielectric response of semiconductors in terms of a screened hopping model relating both to the horizontal transitions in bulk material and to the vertical transitions in space charge regions and at interfaces. This appears to be the only general model consistent with the totality of experimental observations on semiconductors that opens up a new field of theoretical investigations into the nature of electronic transitions in semiconductors and similar materials. It also provides a link with the new interpretation of the more general dielectric response of solids. >