This work will investigate the possibility of using RF spectroscopy with Rydberg atoms to develop a highly accurate, precise electric field probe that has traceability to fundamental physical constants and SI units. E-fields have typically been determined from calculations traced to a power reference, which gives an indirect E-field measurement. The new probe is based on the interaction of RF-fields with Rydberg atoms, where alkali atoms are excited optically to Rydberg states and the applied RF-field alters the resonant state of the atoms. For this probe, the Rydberg atoms are placed in a glass vapor cell. This vapor cell acts like an RF-to-optical transducer, converting an RF E-field to an optical frequency response. The probe utilizes the concept of Electromagnetic Induced Transition (EIT), where the RF transition in the four-level atomic system causes a split of the transition spectrum for the pump laser. This splitting is easily measured and is directly proportional to the applied RF field amplitude. Therefore, by measuring this splitting we get a direct measurement of the RF E-field strength. Because of the accuracy, precision and traceability, this method has the potential to open new areas of science in field measurements. Possible applications for this probe are numerous, ranging from spectrum measurement to biomedical.