Nerve root compression by foraminal pathology is challenging for a surgeon to decompress without violating the facet joint, which may necessitate a fusion procedure. One nonfusion approach to foraminal pathology is a combination intracanal approach for a laminotomy/foraminotomy followed by a paraspinal Wiltse approach for far lateral decompression. Unfortunately, even with the combination approach, it continues to be difficult to achieve adequate decompression without violating much of the facet joint overlying the nerve root. Spine endoscopy offers the ability to decompress the foraminal portion of the nerve without significant violation of the facet joint. We present a surgical video describing the technique for performing a percutaneous endoscopic contralateral L5-S1 foraminal decompression via an interlaminar approach, for a patient presenting with a left L5 radiculopathy due to L5-S1 foraminal stenosis. We explain the differences in the endoscopic channel docking point between ipsilateral and contralateral interlaminar approaches. The steps of an endoscopic foraminotomy are then described: dissect soft tissue and ligamentum flavum off the medial left S1 lamina and superior articulating process (SAP), undercut the superior articulating process of S1 and the inferior articulating process (IAP) of L5 with a drill, resect lateral ligamentum flavum off SAP and IAP exposing epidural fat, and finally dissect the left L5 nerve root and remove compressive lesions throughout its course in the lateral recess, foramen, and laterally. The presentation ends with an intraoperative photograph showing a decompressed L5 nerve root and postoperative imaging confirming this decompression. Appropriate patient consent was obtained.