Background and Aims: Treatment of large esophageal neoplasia is gradually evolving from piecemeal to en bloc resections. Endoscopic submucosal dissection (ESD) is known to achieve more complete resections than piecemeal EMR for large lesions, yet it remains underused in the West because of technical and safety concerns with traditional electrosurgical knives. We aimed to evaluate a novel endoscopic articulating knife used with ESD (ESD-AR) to determine its safety and efficacy for large esophageal neoplasms in comparison with EMR. Methods: We retrospectively studied clinically indicated cases of ESD-AR and EMR for esophageal lesions that were 15 mm or greater. All EMR cases had at least 3 simultaneous EMRs to adequately compare resection area. Rates of perforation, GI bleeding, technical performance, and pre- and postendoscopic resection diagnoses were evaluated. Results: Seventy-two ESD-AR and 72 widespread EMR cases were evaluated for Barrett's esophagus (56%), adenocarcinoma (36%), squamous nodularity (2%), and squamous cell carcinoma (6%). There were no statistical differences in age, sex, Barrett's esophagus length, and lesion or resection size between the 2 groups. No perforations occurred. Two adverse events were recorded with ESD-AR and none with EMR (3% vs 0%, P = .50); these were associated with anticoagulation use (P = .04) and greater resection area (P = .02). There were more upgraded diagnoses post-ESD versus EMR (27% vs 12%, P = .05). Conclusions: ESD-AR by an experienced endoscopist has a comparable safety profile with widespread EMR for large esophageal neoplasia and may have advantages for diagnostic staging.