Anthony Warrens discusses the range of outcomes reported in kidney transplantation trials. Anthony Warrens is Dean for Education and Director of the Institute of Health Sciences Education (IHSE) at Barts and the London School of Medicine and Dentistry (Barts). He is a practising consultant renal physician with a particular interest in transplantation medicine. The need for more organs for transplantation, which has been a continuous concern throughout his clinical career, informed his research agenda.