Electroencephalography (EEG) is a useful tool for the intraoperative monitoring (IOM) of a wide variety of neurosurgical and orthopedic procedures. Several current uses include ischemia detection, titration to suppression during vascular procedures, detection of interictal abnormalities during cerebral neuro-oncology cases, and monitoring for anesthetic depth during spinal surgeries. The information gained from EEG in the operative setting is proportional to the IOM team’s understanding of the modality—its strengths, limitations, and flexibility. Proper IOM EEG interpretation begins with an understanding of the activity that contributes to EEG signal detection at the cellular level, strong adherence to proper electrode placement, and a standardized approach to waveform interpretation.