Liver transplantation is the treatment of choice in acute and irreversible chronic liver failure of distinct etiologies. Because of the current shortage of donor organs, careful selection of candidates for transplantation is required. In addition to specific prognostic models, there are general models, such as the Child-Pugh classification and the MELD system, which are useful in determining the optimal timing of liver transplantation in most patients with cirrhosis. Once the need for transplantation has been determined and the possibility of other available therapeutic measures has been ruled out, a multidisciplinary evaluation should be performed to assess the patient's suitability for this procedure. This evaluation must rule out the presence of medical, surgical or psychological factors that could compromise patient or graft survival, making transplantation futile. The present review analyzes the most frequent contraindications to transplantation, as well as the most important aspects of pretransplantation evaluation.