Living organ donation, that is the removal and transplantation of whole organs or segments of organs that a volunteering donor can live without, has been proposed as an effective and sustainable source of transplantable organs to mitigate the deficit in supply from the traditional cadaveric donor pool. In 2006, the Irish government deemed the development of a national Living Transplant Programme a service priority. The current study aimed to investigate the efficacy of the theory of planned behaviour (TPB) in the context of living organ donation intentions in an Irish sample. One hundred and thirty five undergraduate students (75 females, 60 males; mean age 20.6 years, SD 3.76) completed a self-report questionnaire assessing TPB variables while imagining themselves in a potential living liver donation scenario. In general, attitudes towards living donation were favourable. TPB components explained 44.8% of the variance in intentions. Attitude towards living donation emerged as the strongest predictor of intention. Self-reported levels of knowledge regarding living donation were generally poor. In light of recent EU Communications proposing the expansion of the use of living donors greater understanding of the determinants, psychological implications and ethical considerations in living donation decisions is necessary.