This study presents test–retest reliability statistics and information on internal consistency for new diagnostic modules and risk factors for alcohol, drug, and psychiatric disorders from the Alcohol Use Disorder and Associated Disabilities Interview Schedule-IV (AUDADIS-IV). Test–retest statistics were derived from a random sample of 1899 adults selected from 34,653 respondents who participated in the 2004–2005 Wave 2 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Internal consistency of continuous scales was assessed using the entire Wave 2 NESARC. Both test and retest interviews were conducted face-to-face. Test–retest and internal consistency results for diagnoses and symptom scales associated with posttraumatic stress disorder, attention-deficit/hyperactivity disorder, and borderline, narcissistic, and schizotypal personality disorders were predominantly good (kappa > 0.63; ICC > 0.69; alpha > 0.75) and reliability for risk factor measures fell within the good to excellent range (intraclass correlations = 0.50–0.94; alpha = 0.64–0.90). The high degree of reliability found in this study suggests that new AUDADIS-IV diagnostic measures can be useful tools in research settings. The availability of highly reliable measures of risk factors for alcohol, drug, and psychiatric disorders will contribute to the validity of conclusions drawn from future research in the domains of substance use disorder and psychiatric epidemiology.