The text is designed to help students understand the fundamental nature of behavioral research and the scientific approach to problem solution. It is a treatise on scientific research and problem solving. Stress is on the research problem, the design of research and the relation between the two. The notions of set, relation, variance, probability theory, statistics and measurement present a means to integrate the diverse content of research activity into a unified and coherent whole. Emphasis is on psychological and educational research activity. Particular topics are 1) language and approach of science; 2) sets, relations and variance; 3) probability, randomness and sampling; 4) analysis, interpretation, statistics and inference; 5) analysis of variance; 6) desigbs of research; 7) types of research; 8) measurement; 9) observation and data collection methods; and 10) multiple regression and factor analysis.