This award will fund the design, construction, and optimization of performance of a 21 Tesla ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometer(FTICR-MS). The rationale for this project draws from the workshop, "Science Challenges and Design Concepts for the Next-Generation High-Performance FT-ICR Mass Spectrometer," organized jointly by National High Magnetic Field Laboratory (NHMFL) and the Environmental Molecular Scienes Laboratory (EMSL), and held on 16-17 January, 2008 at NHMFL. Feasibility of the magnet design has been demonstrated by NHMFL's Magnet Science and Technology group, and three vendors have offered to build it. The other components of the spectrometer will be designed and built by NHMFL permanent staff and two postdoctoral researchers. Ion optics design will be guided by large-scale supercomputer simulations (modeling the interaction of more than 1,000,000 ions). This project will improve every aspect of technical performance: sample introduction, ion source(s), ion transmission, ion external accumulation, ion cyclotron resonance (ICR) excitation and detection, computerized and automated instrument control, higher magnetic field, and data reduction. Magnet delivery will take three years, allowing for extensive progress in design of the rest of the instrument in the interim. Applications will focus on petroleomics, top-down proteomics, and hydrogen/deuterium exchange to map contact surfaces in biomacromolecular complexes.