In psychology, self-report measures are structured tools used to assess personality traits by asking individuals to report their thoughts, feelings, and behaviours. These measures rely on the notion that individuals can provide accurate self-assessments, which can then be quantitatively interpreted against established norms. They are widely used in various psychological contexts, including clinical diagnosis, educational assessment, and personal development. The most popular self-report instruments include the Minnesota Multiphasic Personality Inventory (MMPI), the Eysenck Personality Questionnaire (EPQ), and the Sixteen Personality Factor Questionnaire (16 PF). While self-report measures are valuable for their efficiency and ease of use, they can be affected by biases such as social desirability and acquiescence, necessitating careful interpretation by trained professionals.