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A diode-pumped solid state laser is used to deliver excitation at O ex = 671 nm. The beam is expanded by a pair of relay lenses (f 1 = 30 and f 2 = 50 mm) to 3 mm diameter, filling the aperture of a fluid light cable that is coupled to a Hopkins® II rigid endoscope. Near-infrared fluorescence images are collected by the endoscope and transmitted by another set of relay lenses onto a CCD detector that has dimensions of 8.7x6.9 mm 2 (1388x1040 pixels). A zoom lens system (F#1.6-16 aperture) with a tunable focal length (20-100 mm) magnifies the image to fill the dimensions of the CCD. A band pass filter allows fluorescence with spectral range O em = 696 to 736 nm to be collected. The system achieves a resolution of 9.8 P m and field-of-view of 3.6 mm at a dist ance of 2.5 mm between the distal end of the endoscope and the tissue. Images are collected at a ra te of 10 frames per second. A filter wheel is incorporated into the handle of the instrument housing to rapidly switch between reflectance and fluorescence images. Cy5.5-labeled peptides were delivered through the 1 mm diameter instrument channel in the endoscope. Near-infrared fluorescence images demonstrated specific peptide binding to spontaneous adenomas that developed beginning at 2 months of age in a genetically-engineered mouse with mutation of one allele in the APC gene. This integrated methodology represents a powerful tool th at can achieve real time detection of disease in the colon and other hollow organs. Keywords : endoscope, CCD, imaging, fluorescence, ne ar-infrared, real-time, colon, cancer