The article describes the development of a single-electron transistor using a cadmium selenide (CdSe) nanocrystal. The nanocrystals, created through colloidal chemistry techniques, are bound to closely spaced gold leads using bifunctional linker molecules. The charge state of the nanocrystal can be tuned by applying a gate voltage to a degenerately doped silicon wafer, which serves as the gate. Electrical transport measurements show that the conductance peaks at a gate voltage that corresponds to the addition of one electron to the nanocrystal, demonstrating the operation of a single-electron transistor. The measurements also reveal the energy required to add successive charge carriers, providing insights into the energy level spectra of small electronic systems. The study highlights the potential of this device for understanding the behavior of single nanocrystals and the importance of considering exchange and correlation effects in few-hole systems.The article describes the development of a single-electron transistor using a cadmium selenide (CdSe) nanocrystal. The nanocrystals, created through colloidal chemistry techniques, are bound to closely spaced gold leads using bifunctional linker molecules. The charge state of the nanocrystal can be tuned by applying a gate voltage to a degenerately doped silicon wafer, which serves as the gate. Electrical transport measurements show that the conductance peaks at a gate voltage that corresponds to the addition of one electron to the nanocrystal, demonstrating the operation of a single-electron transistor. The measurements also reveal the energy required to add successive charge carriers, providing insights into the energy level spectra of small electronic systems. The study highlights the potential of this device for understanding the behavior of single nanocrystals and the importance of considering exchange and correlation effects in few-hole systems.