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Although many techniques for microanalysis exist, few are totally nondestructive, easy to maintain, or portable. Techniques such as Electron Probe Microanalysis (EPMA) deliver sub-micrometer beams, but are destructive in sample preparation and in analysis, costly, and not portable. In order to create a microanalysis instrument that has low detection limits and is also flexible and portable, we have utilized the benefits of X-ray Fluorescence (XRF) with a capillary focusing optic. Of the many methods used for X-ray focusing, capillary optics best suits a micro-XRF instrument: the devices are compact, easy to implement, focus a divergent beam, and conserve the beam brilliance. The optic is positioned in x,y,z, pitch, and yawdirections to maximize X-ray capture and transmission. The focused beam location and attributes are determined with an X-ray imager. Samples replace the imager at the focal distance and fluorescent radiation is detected with a Si(Li) detector.Motion control, data acquisition, and image acquisition and processing are accomplished on a single PC. Our capillary micro-XRF instrument has successfully analyzed spherical particles down to 10 micrometer diameter. Detection is in therange of 0.1 ng for elements in silicate glasses excited with W tube radiation. The instrument is easily manipulated to accommodate samples in a variety of shapes and sizes and to analyze samples in situ.