This text introduces students to the important theories and philosophies that serve as essential foundations for social inquiry. The author's intention is that each discussion is substantive enough to inspire and motivate readers to think deeper, read more, and wonder more openly. Author Jeong-Hee Kim offers several pedagogical features to help students actively engage with the text such as examples that connect theory to specific research contexts, guidance to help recognize points of convergence and divergence across theoretical traditions, and suggestions to practice thinking with theory.