Shimadzu has taken pioneering role in various kinds of research and development works since a long time in Japan. The company is sole manufacturer of clinical PET systems there. Clairvivo PET is a great development by the company, where the PET system is implemented on small animals in the laboratory. Extremely minute and sensitive measurements can be taken of alterations happening in the animals with Clairvivo PET. When crucial phenomena of an animal are investigated at molecular level, these test results will be important. They are also important for research in drug development and evaluation of efficacy and drug kinetics.