The University of Wisconsin-Madison will establish an Ion Microprobe Laboratory funded by NSF-MRI in partnership with the University. This lab will be the first in the world to dedicate multi-detector/secondary ion mass-spectrometry (SIMS) solely to Stable Isotope Chemistry. Joint university-industry collaboration will push the limits of high accuracy and small spot size through enhancements to the instrument and technique development. Thus, this lab will be uniquely suited to solving important problems. The Wisconsin Ion Microprobe Lab will synergize new applications in Biological Sciences and Engineering, as well as Earth Sciences. Research projects are proposed in areas where in situ ion probe analysis has already proved important, including: petrology, paleoclimatology, meteoritics, materials science, and environmental sciences, as well as in new frontier areas where the potential has not yet been explored, including: plant pathology, nutrition, biochemistry and medicine. A paradox in studies of the Earth and Solar System is that smaller and smaller samples are often critical to answering bigger and bigger questions. The intellectual merit of this project derives from the dramatic reductions of sample size and the ability to put analysis spots into spatial context. This new SIMS capability offers many exciting and revolutionary research opportunities, including, but not limited to: the origins of the atmosphere, oceans, and life on the earliest Earth and Mars; the importance of microbes in biological processing vs. abiotic redox cycling; and the long-term record of atmospheric CO2 and the feedback system between Earth climate change and greenhouse gases. The broader impacts of this proposal involve education at all levels. Many areas of public policy will be impacted including studies of climate change, CO2 sequestration, food adulteration, environmental remediation, health, and national security. The University of Wisconsin has broad outreach programs that will be used to showcase the exciting results from this lab to the general public. ***