Achilles tendinopathy is a common overuse injury that can be classified into mid-portion (non-insertional) and insertional tendinopathy. Mid-portion tendinopathy is primarily associated with sports activities, especially recreational running, whereas insertional tendinopathy frequently also affects middle-aged, overweight individuals. This chapter discusses the pathophysiology, diagnostic methods, and treatment approaches for both types of tendinopathy, with a focus on the role of arthroscopic techniques. Conservative treatments, including eccentric loading exercises and physiotherapy, are effective for many patients. However, a subset of individuals, particularly those with insertional tendinopathy, may benefit from surgical intervention after conservative methods fail. Traditional open surgery has been effective but comes with higher complication rates. In contrast, endoscopic techniques offer less invasive options, providing advantages such as faster recovery and lower complication rates. For mid-portion tendinopathy, endoscopic debridement targeting adhesions, neovascularization, and nerve endings can lead to significant improvement. Insertional tendinopathy may also benefit from endoscopic calcaneoplasty, which removes calcified tissue and addresses bone spurs. In cases of chronic Achilles tendon rupture, the transfer of the flexor hallucis longus (FHL) tendon has shown promising results when performed endoscopically, offering a less invasive alternative to open surgery. This chapter highlights the potential of arthroscopic treatments to effectively manage Achilles tendon injuries, emphasizing the importance of appropriate patient selection and surgical technique for optimal outcomes. Following the description of endoscopic techniques this chapter describes the non-endoscopic (open) surgical techniques of FHL tendon transfer and Proximal Medial Gastrocnemius Release (PMGR).