The current invention provides a new organ preservation solution, suitable for machine perfusion, for maintaining viability of organs, parts of organs and tissues. This solution has been designed to overcome a number of problems associated with hypothermic machine perfusion of donor organs, in particular organs obtained from non-heart-beating donors. The solution prevents or minimizes the adverseaffects caused by ischemia, hypoxia, energy and nutrient depletion, acidification, hypothermia and reperfusion injury. The preservation solutions according to the current invention are superior to current state of the art preservation solutions, in particular for preservat ion and perfusion of organs obtained from non-heart-beating donors, by supplying increased concentrations and an optimized balance of amino acids, vitamins, anti-oxidants, high molecular weight additives and enhanced buffering capacity. In addition, the preservation solution according to the invention combines optimal physical and chemical properties with the use of readily available, inexpensive and pharmaceut ically tested and acceptable compounds, reducing the cost of manufacturing and facilitat ing medical certification of solutions according to the current invention.