Statistical procedures are used in communication science to both describe study results and to make inferences from a study result to some population or process that the investigator is studying. The use of statistics ultimately involves some kind of mathematical operation on numbers and then a translation of those numbers into something interpretable in the context of the study design and its purpose. The numbers in the data set being analyzed are almost always the result of some kind of measurement of the units on one or more constructs. A construct is simply a concept-typically discussed with some kind of verbal label-that we use to describe a psychological, cognitive, biological, or behavioral process or attribute of the object being studied. Media exposure, shyness, attitudes toward censorship, interest in politics, aggression, news learning, gender, nonverbal sensitivity, and family communication patterns are among the many constructs that communication scientists study. It is through the measurement process that we are able to do such things as quantify the association between constructs, compare groups in their behavior, thoughts, or feelings, or otherwise test hypotheses that our intuitions, curiosities, or theories suggest. Because measurement is important to statistics and the scientific process, it is important to understand some of the fundamental concepts in measurement, the topic of this chapter.