Because of the morbidity and mortality that may be associated with esophagectomy, less invasive endoscopic treatment modalities have emerged to treat high− grade dysplasia (HGD) and intramu− cosal cancer (IMC) in Barrett’s esophagus. Endo− scopic resection of focal lesions permits histolo− gical correlation, enabling optimal patient selec− tion [1]. Patients with submucosally invading le− sions should be referred for surgery because they have a 15%±30% risk of having positive local lymph nodes, whereas this risk is minimal in pa− tients with IMC [2, 3]. Endoscopic resection, how− ever, only removes a focal area from the Barrett’s esophagus, leaving the patient at risk of meta− chronous lesions during follow− up [4]. To prevent this, endoscopic resection has been combined with ablative therapy, such as photodynamic therapy (PDT) or argon plasma coagulation (APC), to remove residual (dysplastic) Barrett’s mucosa [5±9]. PDT and APC, however, have sig− nificant shortcomings. First, they often do not re− sult in complete ablation of the whole Barrett’s esophagus [5±9]. Second, studies have shown that oncogenetic alterations, as present in Bar− rett’s esophagus prior to ablation, can still be found in areas of residual Barrett’s esophagus and these may be associated with recurrence of neoplasia [10]. Third, foci of intestinal metaplasia may be hidden underneath the neosquamous mucosa after treatment (this is also known as “buried Barrett”), and some fear that these areas may progress to cancer without being detected endoscopically due to their hidden nature [11, 12]. Lastly, PDT and APC are associated with complications, of which esophageal stenosis is the most relevant [5±9]. Stepwise circumferential and focal radiofrequen− cy ablation (RFA) using the HALO system is a rela− tively new endoscopic treatment modality for Barrett’s esophagus [13±15]. Recent studies sug− gest that this ablation technique is highly effec− tive in removing Barrett’s mucosa and associated dysplasia without the aforementioned draw− backs of other ablation techniques [16±22]. In this review we will explain the technical back− ground of RFA, give a summary of its current sta− tus, and speculate on possible future applica− tions.