The new technique of infrared photothermal beam deflection spectroscopy (PBDS) is described. PBDS is based on the detection of the thermal effects induced at and above an object's surface by the absorption of infrared radiation. In practice, a 2mm-diameter area on an object's surface is irradiated with modulated infrared radiation; the selective absorption of that radiation causes the temperature of the sample spot to rise, so that the air immediately above the sample spot also becomes heated and consequently changes its refractive index. A laser beam passing over the sample spot is therefore deflected. The beam's modulated deflection is detected and measured, the signal resulting in the infrared spectrum of the material of the sample spot. A sample need not be removed from the object, so that PBDS is non-destructive. To demonstrate the utility of PBDS, selected areas on the hilt of a dagger were examined; the infrared spectra of the inlays and matrix permitted the various materials to be identified. The potential utility of the photothermal effect for examining sub-surface structures is pointed out. -- AATA