Electrical cortical stimulation mapping (ECM) is a neurophysiological technique used to help identify the epileptogenic zone (area of brain responsible for a person’s epilepsy). ECM accomplishes this in two ways: (1) direct stimulation of a specified cortical area resulting in the patient’s habitual seizures and (2) the understanding of specific cortical function based on ECM studies. This chapter begins by reviewing neurophysiological concepts underlying ECM. It then continues with an anatomical survey of cortical function as defined by ECM and an explanation of how the identified cortical functions relate to understanding seizure semiology. It proceeds to examine the techniques for electrically provoking seizures and interpretation of such provoked seizures. It concludes by exploring advanced electrophysiological concepts and how they may improve characterization of the epileptogenic zone. In short, this chapter seeks to conceptualize the use of ECM in accurately identifying the epileptogenic zone and informing safe surgical treatment when necessary.