The present study investigated the measurement overlap between the Sixteen Personality Factor Questionnaire (16PF), the Motivation Analysis Test (MAT), and the Eight State Questionnaire (8SQ). These multivariate instruments pertain to the psychological domains of personality, motivation and mood respectively. Canonical/redundancy analysis (Stewart & Love, 1968) was employed on a sample of 258 Australian college students for the 8SQ/MAT measures, and on a subsample of 135 students for the 16PF/MAT and 16PF/8SQ measures. Results demonstrated a marginal overlap in measurement variance for the 16PF and 8SQ, while only very slight redundancy was observed for the 16PF/MAT and 8SQ/MAT intersections. It was concluded that all three instruments are efficient measures of essentially separate psychological modalities.