The increasing organ donor shortage in recent years has forced the use of liver allografts with more expanded criteria for selection which are allocated to sicker and more decompensated recipients, resulting in an increase of the number of transplants. Furthermore advance in surgical techniques have allowed the use of partial liver grafts both split and living donor in order to increase to the donor pool. However, this has resulted in novel challenges and particularly graft dysfunction, graft failure, and small for size syndrome (SFSS) have become more important than ever. Clinically, post-liver transplant graft failure is a continuum ranging from an ambiguous and easily reversible graft dysfunction to a complete absence of function and primary non-function. The incidence of graft dysfunction varies from 13 to 27 % and the incidence of primary non-function affects 4-7 % of the deceased donor liver grafts [1-3]. With living donor liver transplantation, cold and warm ischemia times are minimal and donor quality typically excellent and primary non-function is less common with a 3 % incidence reported in the A2ALL study . However, recipients of living donor liver transplants have a higher incidence of SFSS as cause of early graft failure. Early graft failure in both deceased donor and living donor liver transplant recipients has a major impact on the prognosis and clinical outcome after liver transplantation (LT). This chapter will outline the risk factors for early allograft dysfunction and provide a guide to early diagnosis and management strategies of graft failure and SFSS.