We propose to develop an advanced instrument capable of determining the aerodynamic size, approximate shape, and detailed chemical composition of single bioaerosol particles sampled directly from the ambient atmosphere. The correlated data will be used to classify individual particles and provide a detailed characterization of diverse aerosol populations. Sample preparation will be minimal and the analysis sufficiently rapid that identification can be achieved in near real-time. The experimental methodology will integrate advanced solid-state laser sources and mass spectrometric techniques to fashion a powerful and unique instrument. The resultant device will be used in projects to characterize bioaerosols present in the environment, such as in agricultural workplaces, provide a sensitive detection capability for possible biohazards, and monitor bioaerosol transformations induced by chemical processing in the atmosphere. The capabilities of the proposed instrumentation would greatly facilitate epidemiological studies which seek to correlate bioaerosol exposure with deleterious health effects. Technical Report Available.