In conjunction with our project in laser angiosurgery, our group has demonstrated that laser-induced auto-fluorescence can be a reliable means of distinguishing normal artery from atherosclerotic plaque. Recently a number of groups have become interested in this technique as a means of directing ablation of arterial obstructions in vivo. However, until now, diagnostic spectroscopy has been conducted almost solely on excised cadaveric tissues. As a result, questions still remain about 1) the validity of correlating cadaveric tissue fluorescence spectra with those collected in vivo, and 2) the ability to collect reliable florescence spectra from a subject as dynamic as a living patient.