We study the incidence of delayed graft function (DGF) in a group of 3365 renal transplant recipient patients from various Spanish centres, its clinical consequences, and the evolution in time (transplants performed in 1990, 1994 and 1998) of the factors that determine its presence. The incidence of DGF remained constant in the 3 years studied (30.4, 30.8 and 29.2%, respectively) when contrasting the following factors involved in the establishment of DGF were studied: body mass of recipient, donor age, non-heart beating donation, type of replacement treatment in the pre-transplant period, time of vascular anastomosis and time of cold ischaemia. DGF was not associated with graft or patient survival. In the transplants performed with elderly donors, the cold ischaemia time was associated with greater incidence of DGF, and the latter with less survival of the graft when censored for death. The presence of DGF was significantly associated with acute rejection, cytomegalovirus infection, worse renal function and arterial hypertension at 3 months post-transplantation. In conclusion, the incidence of DGF remained stable in our patients over the years studied and, although not directly, it can affect graft survival as it is associated with acute rejection, arterial hypertension and worse renal graft function. A shortening of ischaemia times may reduce the incidence of DGF and improve transplant results.