Explosives and Chemical Warfare Agents, as well as other chemical and biological threats in airports, in military environments, in government buildings and other public safety places.Raman Spectroscopy employs a non-invasive approach that provides high resolution and specificity.Some applications of IRS and RS includes lab based characterization studies as well as forensic field studies of organic and inorganic substances through their vibration signatures.Optical Fiber Probes (OFP) have been employed in biomedical applications, in communications, in coupling instrumentation to sensing probes and other important modern applications.Moreover, their uses have been extended to excitation and detection of Raman and infrared signals [16,20].Fiber optics applications to Raman Spectroscopy can take advantage of a favorable excitation radiation distribution within the sample; allowing the use of higher laser power levels which, in turn, can yield an elevated signal-to-noise ratio (SNR) for a given experiment without increasing the risk of photo-damaging analytes [21,22].In 2011 Ramírez-Cedeño et al. utilized Optical Fiber Coupled Raman Spectroscopy (OFC-RS) to detect hazardous liquids concealed in commercial products [6].They proved that an optical fiber coupled Raman probe was able to discriminate hazardous liquids inside consumer products from common drinks.Elliason et al. (2007) have also reported drug and liquid explosives detection in concealed in colored plastic containers [23].Recently infrared spectroscopy has shown progress in the use of more powerful IR sources, such as Quantum Cascade Lasers (QCL) by incorporating these devices in IR reflectance, IR transmission and even in IR microscopy applications [24].QCL-based setups are being developed for in the field applications such as breath analysis, environmental research, airborne measurements, security applications, laser-based isotope ratio measurements, and many others.In particular, for security applications, optical methods are advantageous because of their capability for remote and standoff detection [14,25,26].Due to improvements in QCL development, mid infrared lasers operating at room temperature with high output powers in the CW regime are commercially available and make it possible to set up a ruggedized system that allows sensing of explosives and others materials outside the laboratory and the ability to enter real world scenarios.With laser based standoff spectroscopy, the detection distance can be a few meters to tens of meters.Because of the inverse square dependence of light intensity, larger distances require high power, collimated light sources such as lasers.For homeland security applications such as detection of suicide bombers or improvised explosive devices, a distance of 50-100 m is generally sufficient.In this chapter we illustrate the usefulness of incorporating powerful statistical routines to all traditional chemistry disciplines: Chemometrics is the application of statistical tools to plan, execute and analyze experiments in chemistry.To illustrate the power of Chemometrics techniques to analyze experiments in chemistry we have chosen three case studies, all involving identification, quantification, discrimination and classification of chemical threats in different matrices from vibrational spectroscopy multivariate data.In the first case study a remote Raman detection study was performed for quantification of HEM such as pentaerythritol tetranitrate (PETN) present in different mixtures.The remote