Patient was a 69-year-old male with primary hyperparathyroidism. Work-up revealed Ca of 10.2 mg/dL with an elevated PTH at 93 pg/mL (normal: 15-65) and elevated 24-hour urinary Ca. On sestamibi scan, uptake was noted in the left upper (LU) and right lower (RL) parathyroid glands (PGs). Parathyroid autofluorescence-guided 4-gland exploration was planned. Central neck was exposed through a Kocher incision. Near-infrared fluorescence imaging (NIF-I) of the central neck was performed before any further dissection. When the location of a PG was hinted as a bright spot, this location was explored, parathyroid nature confirmed. The order of exploration was left lower (LL), LU, right upper (RU), and RL PGs. LL gland was identified with autofluorescence first, and was initially preserved despite increased size. Similarly, the location of the LU gland was first revealed by autofluorescence. This gland was grossly abnormal and therefore, excised. Then, the right central neck was explored. The RU PG was not detectable on initial visual exploration or by NIF-I, but became apparent on explorative dissection. This gland was also enlarged, but was initially preserved. Finally, the RU parathyroid gland was explored. This was the only gland with normal appearance. The impression was 4-gland hyperplasia, which was further supported by hypercellularity on frozen section and failure of PTH to drop following excision of the LU gland. All 3 glands except the RU were excised and procedure completed. Patient was discharged uneventfully on postoperative day #1. Resected glands were hypercellular on final pathology. Biochemical cure was confirmed on follow-up.