Coronary artery disease leading to ischaemia of the human myocardium is one of the chief causes of morbidity and mortality in the western world. Cellular transplantation has recently been proposed as a novel alternative treatment modality. Adult bone marrow-derived autologous cells are one of the key cell types under investigation in both the experimental and clinical setting. A range of theories has been proposed with regard to the observed myocardial function improvement in both human and animal studies. A concerted interest in scientific questions needs to be constructed on the regenerative information made available throughout the last years. It is only now that we begin to fully understand this fast growing body of research and how it may have wide ranging implications for the treatment of ischemic heart disease.