Based on the results of prior research, we examined relationships between Personality Assessment Inventory (PAI) items on clinical scales of antisocial features (ANT) and anxiety‐related disorders (ARD) with patient‐ and therapist‐rated alliance early in treatment (third or fourth session). We also explored the relationship between the PAI treatment rejection scale (RXR) and early session therapist‐rated alliance, despite null findings in previous work. We used PAI protocols from a clinical outpatient sample (N = 80). Data were analysed using backwards linear regressions. Results indicated that a group of ANT items from different ANT subscales predicted patient‐rated therapeutic alliance, F(8,59) = 5.182, p = .000, R2 of .413, f2 = 0.70. Additionally, a group of ARD items from different ARD subscales significantly predicted therapist‐rated alliance, F(6,62) = 3.007, p = .012, R2 of .225, f2 = 0.29. No significant relationships were found for RXR items and therapist‐rated alliance, consistent with prior findings. Clinical implications are discussed.