Descriptive statistics play an important role in empirical social research. This volume introduces its fundamental concepts and measures. One of the concepts presented is the statistical relationship (association, correlation). Given the significance of this concept, the explanation of commonly used and computable association or correlation coefficients with relevant computer programs occupies the largest portion of this manuscript. Special attention is given to those association measures that can be interpreted in terms of proportional reduction in error, referred to as PRE measures (proportional reduction in error measures). The presentation concludes with an introduction to the classical analysis of multivariate tables, also known as control of third variables or elaboration.