Personality Assessment Inventory (PAI), developed by Leslie Morey (1991, 2007), is a self-report 344-item personality test that assesses a respondent's personality and psychopathology. Each item is a statement about the respondent that the respondent rates with a 4-point scale (1-"Not true at all, False", 2-"Slightly true", 3-"Mainly true", and 4-"Very true"). It is used in various contexts, including psychotherapy, crisis/evaluation, forensic, personnel selection, pain/medical, and child custody assessment. The test construction strategy for the PAI was primarily deductive and rational. It shows good convergent validity with other personality tests, such as the Minnesota Multiphasic Personality Inventory and the Revised NEO Personality Inventory.

The PAI has 22 non-overlapping scales of four varieties: 1) validity scales, 2) clinical scales, 3) treatment consideration scales, and 4) interpersonal scales.

The validity scales measure the respondent's overall approach to the test, including faking good or bad, exaggeration, defensiveness, carelessness, or random responding.

There are also four supplementary validity scales:

Further identification of exaggeration and/or negative bias can be calculated used the NIM Predicted Profile

Additionally, one can also apply the use of the Negative Distortion Scale

The clinical scales measure the respondent's psychopathology using diagnostic categories that were judged by the developers to be relevant based on their historical and contemporary popularity among psychologists. Each clinical scale (except Alcohol Problems and Drug Problems) represents a particular trait, and each scale has sub-scales that represent more specific aspects of that trait.

The treatment consideration scales measure factors that may relate to treatment of clinical disorders or other risk factors but which are not captured in psychiatric diagnoses.