A model of tissue fluorescence has been developed using information collected from three different categories: fluorescence microspectroscopy, fluorescence microscopic imaging, and tissue optics. We have shown that, by combining these, one could model clinically observed tissue fluorescence collected with fiber optic probes at endoscopy of mucosal tissues. By reversing the modeling procedure, we have shown that pathologic information such as amount of hemoglobin, mucosal depth, extent of dysplastic changes, and the volume occupied cells can be extracted from fluorescence spectra. In order to improve the model, reflectance spectrosocpic studies are incorporated in the fluorescnece measurements. This approach, we term "optical histology" is being extended to mucosal organs for study of dysplasia.