The aim of this paper is to present further data for the validation of the Interpersonal Guilt Rating Scale-15 self-report (IGRS-15s; Gazzillo et al., 2018). We recruited a sample of 448 subjects, to whom we administered the IGRS-15s together with other empirically validated measures for the assessment of social desirability, shame, self-esteem, empathy, mental health and therapeutic alliance. In line with our hypotheses, the previously established three-factor structure of the IGRS-15s (Survivor guilt, Omnipotence guilt, and Self-hate) was confirmed. Moreover, the internal consistency and test-retest reliability of IGRS-15s were adequate to good. All the IGRS-15s factors were negatively correlated with self-esteem and mental health and positively correlated with shame; Survivor guilt and Omnipotence guilt were positively correlated with empathy; Survivor guilt and Self-hate negatively affected therapeutic alliance; and different traumas had different, theoretically predictable, impacts on the different kinds of guilt. Overall, these data support the reliability and validity of the IGRS-15s.