cal function in vivo can facilitate the development and implementation of such tailored treatment. However, while history highlights the payoff and public benefit from government investments in science and technology for nuclear medicine, the competitive edge that the United States has held for the past 50 years is seriously challenged. Three major impediments have been identified:

1. There is no short- or long-term programmatic commitment by any agency to funding chemistry, physics, and engineering research and associated high-technology infrastructure (accelerators, instrumentation, and imaging physics), which are at the heart of nuclear medicine technology research and development.

2. There is no domestic supplier for most of the radionuclides used in day to day nuclear medicine practice in the United States and no accelerator dedicated to research on medical radionuclides needed to advance targeted molecular therapy in the future.

3. Training for nuclear medicine scientists, particularly for radiopharmaceutical chemists, has not kept up with current demands in universities and industry, a problem that is exacerbated by a shortage of university faculty in nuclear and radiochemistry.

Thus, although the scientific opportunities have never been greater or more exciting, the infrastructure on which future innovations in nuclear medicine depend hangs in the balance. If the promise of the field is to be fulfilled, a federally supported infrastructure for basic and translational research in nuclear medicine should be considered.