Molecular Imaging emerged in the early twenty-first century as a discipline at the intersection of molecular biology and in vivo imaging. It enables the visualisation of the cellular function and the follow-up of the molecular process in living organisms without perturbing them. The multiple and numerous potentialities of this field are applicable to the diagnosis of diseases such as cancer, and neurological and cardiovascular diseases. This technique also contributes to improving the treatment of these disorders by optimizing the pre-clinical and clinical tests of new medication. They are also expected to have a major economic impact due to earlier and more precise diagnosis. Molecular and Functional Imaging has taken on a new direction since the description of the human genome. New paths in fundamental research, as well as in applied and industrial research, render the task of scientists more complex and increase the demands on them. Therefore, a tailor-made teaching program is in order.

 Molecular imaging differs from traditional imaging in that probes known as biomarkers are used to help image particular targets or pathways. Biomarkers interact chemically with their surroundings and in turn alter the image according to molecular changes occurring within the area of interest. This process is markedly different from previous methods of imaging which primarily imaged differences in qualities such as density or water content. This ability to image fine molecular changes opens up an incredible number of exciting possibilities for medical application, including early detection and treatment of disease and basic pharmaceutical development. Furthermore, molecular imaging allows for quantitative tests, imparting a greater degree of objectivity to the study of these areas. One emerging technology is MALDI molecular imaging based on mass spectrometry.

 Many areas of research are being conducted in the field of molecular imaging. Much research is currently centered around detecting what is known as a predisease state or molecular states that occur before typical symptoms of a disease are detected. Other important veins of research are the imaging of gene expression and the development of novel biomarkers. Organizations such as the SNM Center for Molecular Imaging Innovation and Translation (CMIIT) have formed to support research in this field. In Europe, other "networks of excellence" such as DiMI (Diagnostics in Molecular Imaging) or EMIL (European Molecular Imaging Laboratories) work on this new science, integrating activities and research in the field. In this way, a European Master Programme "EMMI" is being set up to train a new generation of professionals in molecular imaging.

 Recently the term "Molecular Imaging" has been applied to a variety of microscopy and nanoscopy techniques including live-cell microscopy, Total Internal Reflection Fluorescence (TIRF)-microscopy, STimulated Emission Depletion (STED)-nanoscopy and Atomic Force Microscopy (AFM) as here images of molecules are the readout.