This chapter is designed to provide a background in main areas of testing and instrumental analysis used for polymer processing. The following are the characterization techniques to be presented and covered: Fourier transform infrared spectroscopy – FTIR, chromatography, thermal analysis (differential scanning calorimetry – DSC and thermogravimetry – TGA), and rheometry. Combined with an engineering background, this chapter has the concise information and industrial case studies for data analysis using the most important characterization techniques.