"Laser-induced breakdown spectroscopy (LIBS) represents a powerful tool for qualitative analysis and can achieve quantitative results with acceptable accuracy and precision. Nevertheless, due to the high laser pulse energies used in LIBS, sample damage represents a drawback for some applications. In recent years, novel techniques, such as Double Pulse LIBS (DP-LIBS), have been developed to overcome main LIBS drawbacks. In order to diminish sample damage, this dissertation studies the use of signals from orthogonal DP-LIBS obtained at low ablative energies for quantitative analysis by a selfcalibrated method called Calibration Free (CF)-LIBS. Before testing DP-LIBS with CF-LIBS, this dissertation presents the implementation of conventional single pulse LIBS (LIBS or SP-LIBS) as well as orthogonal DP-LIBS approaches. For optimal implementation of quantitative analysis, two problems are solved by different techniques (calibration curves and CF-LIBS). In the first case, a series of experiments, based on calibration curves technique, were conducted to quantify the Active Pharmaceutical Ingredient (API) in commercial pellets by estimating their Cl content. Results from LIBS were compared and validated with those obtained by High Performance Liquid Chromatography (HPLC). In the second problem, CF-LIBS is presented as a technique capable of determining the chemical composition of multi-elemental samples. Fe, Cr, Mn, and V elements from a steel sample were successfully quantified. Results obtained by CF-LIBS satisfactorily agree with microprobe technique results and certified elemental values in the sample."