Progress of the scintillation camera is described, as an in vivo imaging device in nuclear medicine. Usefulness of the scintillation camera in vivo imaging was established by appearance of technetium 99m labeled pharmaceuticals. As regards the total counting efficiency, gamma-ray energy of Tc 99m is ideal for the scintillation camera in vivo detection. Proper half life of Tc 99m reduces the radiation dose to patients. Progress in spatial resolution of the camera is strongly dependent on improvements in performance of the photomultiplier tube. Also, various distortion corrections are performed using advanced microprocessor technologies. The biggest progress regarding the scintillation camera is in the change in the shape of the field of view that has been change from round to rectangular. Presently, almost of newly installed scintillation cameras have a single photon emission computed tomograph capability. We look forward to new innovations in in-vivo imaging in the future.