Inclusion Criteria:  Participant is age 12 and older. Participant is male or is a female of childbearing potential who is surgically sterile, 2 years postmenopausal, or practices a reliable method of contraception (hormonal, barrier method or abstention). Participant failed treatment with a minimum of two antiseizure medications (used in appropriate doses) with adequate monitoring of compliance and the effects of treatment, as determined by the investigator. Participant is able to maintain an electronic diary alone or with the assistance of a competent individual. Participant is able to attend clinic appointments in accordance with the study schedule. Participant or parent(s) or legal representative have signed an IRB approved written informed consent/assent. The informed consent form or specific assent form, where required, will be signed and dated by minors. Participant is not currently implanted with an RNS Neurostimulator or NeuroPace Leads. In the investigator's opinion, participant is able to tolerate a neurosurgical procedure. Participant with a confirmed diagnosis of idiopathic generalized epilepsy experiencing primary generalized tonic-clonic seizures, with or without myoclonic or absence seizures, consistent with the International League against Epilepsy Revised Classification of Seizures (2017). Participant has had 2 or more generalized tonic-clonic seizures during the two month retrospective baseline. Participant has had a routine electroencephalogram (EEG) within 2 years prior to enrollment with electroencephalographic features consistent with idiopathic generalized epilepsy; other concomitant anomalies must be explained by adequate past medical history. Participant has been on a stable antiseizure medication (ASM) regimen during the two month retrospective baseline and is willing to remain on a stable ASM regimen during the prospective Baseline and throughout the Effectiveness Evaluation Period, if medically possible; rescue benzodiazepine medications for acute seizure clusters are permitted. Participant has undergone computed tomography (CT) or magnetic resonance imaging (MRI) within 10 years prior to enrollment that ruled out a progressive cause of epilepsy or an abnormality likely to be associated with focal-onset seizures. Participant does not have a vagus nerve stimulator (VNS, LivaNova) or Participant's VNS is OFF during the two month retrospective baseline and participant is willing to keep the VNS off during the study.  Exclusion Criteria:  Participant is pregnant. Participant is participating in a therapeutic investigational drug or other device study. Participant is implanted with an electronic medical device that delivers electrical energy to the brain. Participant requires procedures that are contraindicated based on current RNS System labeling. Participant has been diagnosed with active psychosis, major depression or suicidal ideation in the preceding year. Participants with post-ictal psychiatric symptoms need not be excluded. In the opinion of the investigator, the participant has a clinically significant or unstable medical condition (including alcohol and/or drug abuse) or a progressive central nervous system disease. Participant has a history of partial-onset seizures or EEG findings within the past 2 years indicative of partial-onset or symptomatic generalized abnormalities. Participant has been diagnosed with psychogenic or non-epileptic seizures in the preceding year. Participant has experienced unprovoked status epilepticus in the preceding year. Participant is taking any anticoagulants.