Single-electron devices in silicon provide a means to control the electrons in nanoscale electronic systems precisely while retaining compatibility with large-scale integrated (LSI) circuit technology. Single-electron transistors operating at room temperature have now been fabricated in silicon-on-insulator, polycrystalline silicon, and nanocrystalline silicon material. Memory cells where the stored states are defined by single electrons, and few-electron memory cell arrays with integrated sense amplifiers have been demonstrated. Few-electron logic gates using novel ‘binary-decision diagram’ logic circuits have also been fabricated. These devices explore the ultimate limits of electronic systems and raise the possibility of LSI circuits with nanoscale, single-electron elements.