Background Although peroral endoscopic myotomy (POEM) is highly effective for the management of achalasia, clinical failures may occur. The optimal management of patients who fail POEM is not well known. This study aimed to compare the outcomes of different management strategies in patients who had failed POEM. Methods This was an international multicenter retrospective study at 16 tertiary centers between January 2012 and November 2019.All patients who underwent POEM and experienced persistent or recurrent symptoms (Eckardt score>3) were included. The primary outcome was to compare the rates of clinical success (Eckardt score ≤3) between different management strategies. Results 99 patients (50 men [50.5%]; mean age 51.4 [standard deviation (SD) 16.2]) experienced clinical failure during the study period, with a mean (SD) Eckardt score of 5.4 (0.3). A total of 29 patients (32.2%) were managed conservatively and 70 (71%) underwent retreatment (repeat POEM 33 [33%], pneumatic dilation 30 [30%], and laparoscopic Heller myotomy (LHM) 7 [7.1%]). During a median follow-up of 10 (interquartile range 3-20) months, clinical success was highest in patients who underwent repeat POEM (25/33 [76%]; mean [SD] Eckardt score 2.1 [2.1]), followed by pneumatic dilation (18/30 [60%]; Eckardt score 2.8 [2.3]), and LHM (2/7 [29%]; Eckardt score 4 [1.8]; P =0.12). A total of 11 patients in the conservative group (37.9%; mean Eckardt score 4 [1.8]) achieved clinical success. Conclusion This study comprehensively assessed an international cohort of patients who underwent management of failed POEM. Repeat POEM and pneumatic dilation achieved acceptable clinical success, with excellent safety profiles.