If supersymmetry is discovered at the LHC, the extraction of the fundamental parameters will be a formidable task. In such a system where measurements depend on different combinations of the parameters in a highly correlated system, the identification of the true parameter set in an efficient way necessitates the development and use of sophisticated methods. A rigorous treatment of experimental and theoretical errors is necessary to determine the precision of the measurement of the fundamental parameters. The techniques developed for this endeavor can also be applied to similar problems such as the determination of the Higgs boson couplings at the LHC.