In the past decade, use of biomarker fingerprinting techniques to study spilled oils has rapidly increased and biomarker parameters are playing a prominent role in almost all oil spill-related environmental forensic studies and investigations. This chapter discusses diagnostic ratios of biomarkers and cross-plots of biomarkers, unique biomarkers, weathering effects on biomarker distribution, and application of biomarker fingerprinting techniques for spill source identification, oil correlation, and differentiation using univariate and multivariate methods. Data analysis is an important part of chemical fingerprinting and a broad collection of statistical techniques are used for evaluation of data in real oil spill cases. Data evaluation techniques within environmental forensics and specifically for spill identification, oil correlation, and differentiation have traditionally centered on univariate methods and comparison of diagnostic ratios and complex profiles for subjective pattern matching. It can be anticipated that ongoing developments can further enhance the utility and defensibility of oil hydrocarbon fingerprinting.