Poly(ADP-ribose) polymerase-1 (PARP-1) is one of the most abundant proteins within mammalian cells. First described more than 45 years ago, PARP-1 has been the subject of many studies and was shown to be involved in multiple aspects of cellular metabolism. Despite many interesting studies that implicate PARP-1 in transcription, chromatin remodelling, apoptosis, DNA repair and several neurological disorders, its precise role is still unclear. This review will discuss the role of PARP-1 in DNA repair and propose a model whereby PARP-1 operates as a modulator of base excision repair capacity.