As diagnostic techniques evolve from the systems to the molecular level, the role of multimodality molecular imaging becomes increasingly important. PET, SPECT and MRI are powerful techniques for in vivo molecular imaging. The hybrid combination of PET (or SPECT) and MRI, enabling truly simultaneous acquisition, will bridge the gap between molecular and systems diagnosis. By continuing the successful tradition of the Julich meetings held in 2008 and 2010 and of the Knoxville workshop in 2011, we have organized the first Conference on PET-MR and SPECT-MR in sharing by Pisa University-INFN, the COST Action PET-MRI (funded by EU for 4 years 2011-2014) and Juelich Forschungszentrum. This conference is scheduled for May 26-30, 2012 in the ELBA island, near Pisa (Italy) and is the first of a series that will be run as annual conference. The next one will be in Julich in 2013 and the following one in Greece in 2014. The conference will cover all the technological and applicative aspects of both sequential and simultaneous PET/MR and SPECT/MR systems. Both clinical and preclinical applications will be discussed at length. An industrial session will be set up where the various companies can provide the latest information on their products in this field. Finally there will be also presented the latest results on the continuous search for new tracers and especially for bi-modal tracers that could give the greatest advantages for the hybrid systems.