This secondary analysis of 5,000 African Americans and black Caribbeans explored how their use of social work services to address mental and substance use disorders was associated with the disorder involved as well as their perceived need for services, belief system, family resources, proximity to services, social-structural factors, and demographic characteristics. The sample was extracted from a national data set. Results of multinomial logistic regression showed that use of social work services was increased by dual diagnosis, substance use disorder alone, and mental disorder alone; by deteriorating mental health; by perceived stigma in treatment use; by welfare receipt and insurance coverage for mental health services; and by college graduation. Results also showed that use of services outside social work was promoted by dual diagnosis, substance use disorder alone, and mental disorder alone; by deteriorating mental health; by experience of racial discrimination; by insurance coverage for mental health services; by college education or graduation; and by female gender and increasing age. The findings' implications for social work intervention and education are discussed.