Preoperative assessment and localization is crucial in the management and outcome of patients with duodenal gastrinoma. Localization can be challenging because of small size and variable location. We describe our experience of managing 1 such patient by localizing the lesion during the preoperative period. Side-viewing endoscopy, endoscopic ultrasound, and somatostatin receptor scintigraphy determined the exact location of the tumor, which was confirmed during surgery on palpation, endoscopic transillumination, and duodenotomy. Antrectomy was performed, and the patient was asymptomatic after 8 months of follow-up and did not require antisecretory medications. His serum gastrin levels returned to normal during the postoperative period.