This chapter discusses the complications of meshes for repairing large hiatal defects when suture repair is inadequate. While many studies report the benefits of mesh repair in reducing the recurrence of hiatus hernia with a low complication rate, some complications can be catastrophic. Complications such as intraluminal mesh erosion can be difficult to manage and may require oesophageal resection. The chapter presents two cases illustrating these complications: one involving mesh causing pseudoachalasia, and another of mesh erosion into the oesophagus. These cases underscore the complexity of managing mesh-related issues, often requiring extensive surgical intervention to address symptoms and prevent further complications. Key learning points emphasize the importance of careful evaluation and surgical planning in such cases to mitigate risks and optimize patient outcomes.