The first decade of the century has been the beginning of an era of new practice in daily medical imaging, that is the multimodality involving functional or metabolic imaging brought by nuclear medicine techniques directly associated with anatomical information brought by CT (Computed X-Ray Tomography) devices combined with nuclear medicine detectors. PET (Positron Emission Tomography)/CT and SPECT (Single Photon Emission Computed Tomography)/CT are now established to further increase the interest of PET and SPECT, thanks to improved localization of the pathologic processes, and in many instances thanks to a gain in specificity. An even better use of the combined information will necessitate redefining some protocols and indications, and the future will probably see the continued development of multimodality imaging in practice. Besides the combination with CT, another modality is expected in the future: PET/MRI (Magnetic Resonance Imaging).