**Study Summary:** This study is looking into a new way to help people with *Treatment-Resistant Depression (TRD)*, which means depression that doesn't get better with usual treatments. The study will test the safety and effectiveness of the Motif XCS System, a device that sends signals to the brain to help improve mood. It's an early test to see if it could work for people with serious depression. **Key Points:** - Participation involves using the Motif XCS System and attending follow-up visits for at least 4 weeks. - You must be between 22 and 85 years old and have tried at least two different depression treatments without success. - There are specific health conditions and treatments that may prevent participation, like having certain implants, being pregnant, or planning to undergo other brain therapies. If you have questions about the device or whether you should join, a doctor can help explain if this study is right for you.