Like any other research tool, observational methods can be misused. Professors Yoder and Symons have put together a textbook that introduces graduate students to the competent conduct of observational research methods and measurement. Their approach embraces both single-subject and group-design perspectives of observational methods, instructing students when and how to use both methodologies. In addition, the authors include many practical exercises within chapters as well as a CD Rom that includes media files of an observation session to code with multiple behavior sampling methods.