Direct, well-organized, and easy to follow, , by Bruce Mc Keown and Dan B. Thomas, reviews the philosophical foundations of subjective communicability (concourse theory), operant subjectivity, and quantum-theoretical aspects of Q as relevant to the social and behavioral sciences. The authors discuss data-gathering techniques (communication concourses, Q samples, and Q sorting), statistical techniques (correlation and factor analysis and the important calculation of factor scores), and strategies for conducting small person-sample research along Q methodological lines.