Inclusion Criteria:

• Subject has disabling motor simple partial seizures, complex partial seizures, and/or  secondarily generalized seizures. Disabling refers to seizures that are severe enough  to cause injuries, or significantly impair functional ability in domains including  employment, psychosocial education and mobility.
• Subject has seizures that are distinct, stereotypical events that can be reliably  counted, in the opinion of the investigator, by the subject or parent/caregiver.  
• Subject had an average of three or more disabling motor simple partial seizures,  complex partial seizures and/or secondarily generalized seizures over the two most  recent consecutive 30-day periods, with no 30-day period with less than two seizures  per subject and/or parent/caregiver report.  
• Subject failed treatment with a minimum of two anti-seizure medications (used in  appropriate doses) with adequate monitoring of compliance and the effects of  treatment, as determined by the investigator.  
• Subject has undergone diagnostic testing as part of his/her standard care that has identified no more than two epileptogenic regions.  
• Subject is male or a female of childbearing potential using a reliable method of  contraception (hormonal, barrier method, surgical or abstention).  
• Subject is age 12 or older but will be less than age 18 (has not reached 18th  birthday) at the time of implantation with the RNS System.  
• Subject is able to maintain an electronic diary alone or with the assistance of a  competent individual.  
• Subject is able to attend clinic appointments in accordance with the study schedule.  
• Subject and/or parent/guardian must be willing and able to provide informed consent  and assent when appropriate.
• Subject is not currently implanted with an RNS Neurostimulator or NeuroPace Leads.  
• In the investigator's opinion, subject is able to tolerate a neurosurgical procedure.  

Exclusion Criteria:  

• Subject has been diagnosed with primarily generalized seizures.  
• Subject requires procedures that are contraindicated based on current RNS System  labeling.
• In the opinion of the investigator, the subject has a clinically significant or unstable medical condition (including alcohol and/or drug abuse) or a progressive central nervous system disease.
• Subject has been diagnosed with active psychosis, major depression or suicidal ideation in the preceding year. Subjects with post-ictal psychiatric symptoms need not  be excluded.
• Subject is pregnant.  
• Subject is participating in a therapeutic investigational drug or other device study.
• Subject is implanted with an electronic medical device that delivers electrical energy to the brain.
• Subject has been diagnosed with psychogenic or non-epileptic seizures.  
• Subject has experienced unprovoked status epilepticus in the preceding year.  
• Subject is taking chronic anticoagulants.  
  • Note: For contraindications, refer to current physician labeling (manuals) for the RNS System available at the NeuroPace website (www.neuropace.com).