Sinus lift is procedure for lifting the maxillary sinus floor in patients with a lack of available bone height in lateral part of maxilla due to pneumatization of the alveolar processus after tooth loss. The aim of this procedure is to create necessary bone height to allow implantation of appropriate implant lenght. For proper procedure it is necessary to know the bone and membrane anatomy of the maxillary sinus and the position of blood vessels and nerves. Prior to the procedure, it is necessary to make a detailed preoperative preparation which includes anamnesis, clinical examination and radiological evaluation including CBCT and RTG. Two main sinus lift techniques are open or lateral approach and closed or Summers technique. In both techniques, there are a number of modifications primarily related to access to the sinus floor and the use of augmentation materials and their combination. Both closed and open technique have some complications among which the most common are perforation of the Schneiderian membrane, bleeding and postoperative infections. It is important to know the prevention and treatment of possible complications