Paul Costa is a prominent psychologist known for his work in personality psychology. He is best recognized for developing the Five Factor Model of personality, which outlines five key traits: openness, conscientiousness, extraversion, agreeableness, and neuroticism. This model has been widely used in both research and practical applications, helping to understand human behavior and personality differences. In addition to his research, Paul Costa has contributed to various academic publications and has collaborated with other psychologists, including Robert McCrae. Together, they have advanced the field of personality assessment, providing tools that are used in clinical settings and organizational psychology to evaluate individual differences.