<P>Human Development and Family Science (HDFS) is an interdisciplinary and applied field that draws from developmental science, family science, and other social sciences. <I>Research Foundations of Human Development and Family Science </I>is a textbook that provides an introduction to the diverse scientific research methods that form the foundation of scholarship and practice in HDFS. </P><P></P><P>In Part I, Kathleen D. Dyer explores science. She distinguishes empirical scientific research from common sense and from knowledge gained from personal experience. This section also includes a discussion of the strategies used by pseudoscience to exploit the well-deserved credibility of science, providing relevant examples. Part II examines systematic empiricism through sampling and measurement. HDFS scholars use a wide array of measurement tools, including self-report (interviews, questionnaires, and self-report tasks), observations (participant, naturalistic, and structured), obj