This document discusses the importance of guidance and counseling services in helping individuals live happy, balanced, and effective lives. It notes that people differ in psychological attributes and individual differences can be measured and studied to explain and predict behavior. Individual difference psychology examines how people are similar and differ in their thinking, feeling, and behavior. Some key individual differences discussed include locus of control, self-monitoring, self-esteem, needs for achievement, affiliation, and power, attitudes, values, and defense mechanisms.