Small biogenic changes in voltage such as action potentials in neurons can be monitored using extracellular single unit recording techniques. This technique allows for investigation of neuronal electrical activity in a manner that is not disruptive to the cell membrane, and individual neurons can be recorded from for extended periods of time. This chapter discusses the basic requirements for an extracellular recording setup, including different types of electrodes, apparatus for controlling electrode position and placement, recording equipment, signal output, data analysis, and the histological confirmation of recording sites usually required for in vivo recordings. A more advanced extracellular recording technique using piggy-back style multibarrel electrodes that allows for localized pharmacological manipulation of neuronal properties is described in detail. Strategies for successful signal isolation, troubleshooting advice such as noise reduction, and suggestions for general laboratory equipment are also discussed.