Magnetic sphincter augmentation (MSA) offers a minimally invasive anti-reflux alternative to fundoplication for gastroesophageal reflux disease. The most common side effect of MSA is dysphagia, which may require dilation or even device removal. The incidence of dysphagia may be reduced by MSA sizing and preoperative motility studies. Multiple rapid swallows (MRS) is a provocative maneuver during high-resolution esophageal manometry (HRM) that assesses peristaltic reserve. We evaluated factors predicting development of dysphagia following MSA.