An advanced infrared interferometric method using fiber optics has been developed for biomedical, environmental and industrial applications. The fiberoptic Evanescent Wave Fourier Transform Infrared (FEW-FTIR) spectroscopy method has been applied to diagnostics of numerous materials including living tissue without sample preparation. This highly sensitive diagnostics tool can conduct surface and subsurface analysis at the molecular level on such diverse materials as human tissue and body fluids, plants, soil, rocks, chemicals, oil, paper and polymers nondestructively, noninvasively in vivo. Operating in the attenuated total reflection regime in the middle-infrared range, the FEW-FTIR technique provides direct contact between the fiber probe and any surface. Our fiber optical spectroscopic device is compact, portable for any application and operates up to a distance of three meters with extremely low loss and nontoxic fibers. This method allows the detection of functional chemical groups and bonds directly from a surface by soft touching of a surface for 15 sec. Applications of this method include (1) early diagnostics of precancerous conditions and other diseases, (2) sun, laser radiation and the influence of other environmental factors (water, pollution and weather), (3) quality control during manufacturing processes, in process analysis.