After rotator cuff repair, few patients require revision surgery, and failure to heal does not always translate into clinical failure, although healing is associated with better outcomes. Failure of rotator cuff repair is perceived differently by the patient, by the surgeon, and in terms of social and occupational abilities. The work-up of failed cuff repair differs little from the standard work-up of cuff tears. Information must be obtained about the circumstances of the first repair procedure, a possible diagnostic inadequacy and/or technical error, and early or delayed trauma such as an aggressive rehabilitation programme. Most cuff retears do not require surgery, given their good clinical tolerance and stable outcomes over time. Repeat cuff repair, when indicated by pain and/or functional impairment, can improve pain and function. The quality of the tissues and time from initial to repeat surgery will influence the outcomes. The ideal candidate for repeat repair is a male, younger than 70 years of age, who is not seeking compensation, shows more than 90̊ of forwards elevation, and in whom the first repair consisted only in tendon suturing or reattachment. In addition to patient-related factors, the local conditions are of paramount importance in the decision to perform repeat surgery, notably repeat suturing. The most favourable scenario is a small retear with good-quality muscles and tendons and no osteoarthritis. When these criteria are not all present, several options deserve consideration as potentially capable of relieving the pain and, to a lesser extent, the functional impairments. They include the implantation of material (autograft, allograft, or substitute), a muscle transfer procedure, or reverse shoulder arthroplasty. However, the outcomes are poorer than when these options are used as the primary procedure. Prevention is the best treatment of cuff repair failure and involves careful patient selection and a routine analysis of the treatments that may be required by concomitant lesions. Biceps tenotomy should be considered on a case-by-case basis. Smoking cessation should be strongly encouraged and any metabolic disorders associated with repair failure should be brought under control.