The scientific study of crime implies the ability to measure it. In this Quantitative and Qualitative Research Techniques class, students are expected to acquire the cognitive and procedural skills that will allow them to overcome the epistemological, methodological and technical difficulties inherent to the analysis of delinquency. Crime is a complex and multidimensional concept as it is related to an heterogenious range of behaviors, variables and phenomena. In many cases, the scientist finds it difficult to access criminological quantitative or qualitative data since crime is often a phenomenon or behavior that remains hidden. Moreover, there is no unification in the data sources that often provide with partial or incomplete information.