An organ perfusion apparatus and method monitor, sustain and/or restore viability of organs and preserve organs for storage and/or transport. Other apparatus include an organ transporter, an organ cassette and an organ diagnostic device. The method includes perfusing the organ at hypothermic and/or normothermic temperatures, preferably after hypothermic organ flushing for organ transport and/or storage. The method can be practiced with prior or subsequent static or perfusion hypothermic exposure of the organ. During the period in which the organ is preserved and/or maintained, the organ may be additionally be perfused to obtain data regarding the fluid and/or organ. The data may then be used to ultimately provide information regarding the perfusion efficacy and allow for altering of the perfusion parameters.