Behavior analysis provides a unique way of coming to understand intrapersonal and interpersonal communication behaviors, and focuses on control techniques available to a speaker and counter-control techniques available to a listener. "Time-series methodology" is a convenient term because it subsumes under one label a variety of baseline or baseline-related methods that share fundamental features. In its simplest form, the baseline methodology consists of a two-step (A-B) design: step A involves gathering baseline data, and step B involves gathering post-baseline (or intervention) data. However, more elaborate designs are needed to demonstrate validity. The ABAB design is a basic AB design with one replication. The ABCD design is important because it provides similar baseline and post-baseline data as well as providing replicability and control without the need to return to original baselines. The ABCD design can be employed to measure the effectiveness of an intervention across two or more behaviors, individuals, and/or settings. Time-series methods are particularly well-suited to answer three kinds of questions: (1) Is a particular environmental variable functionally related to the occurrence of a particular behavioral variable? (2) What is the shape of a functional relation between an environmental and a behavioral variable? and (3) What are the quantitative values associated with these relationships? While time-series methods are helpful in answering particular kinds of questions, it would be a mistake to conclude that these methods should be employed in all situations. (Four graphs are attached.) (RS)