Relatively little is known about the prevalence and clinical characteristics of dependence on sedative-hypnotics, and almost nothing has been published regarding abuse. This report relates information on Diagnostic and Statistical Manual of the American Psychiatric Association (DSM-IIIR) sedative-hypnotic use disorders among subjects from the Collaborative Study on the Genetics of Alcoholism (COGA). A standardized interview was used to generate data on 407 men and women in Group 1 with sedative-hypnotic dependence (4.4% of the COGA sample), 34 in Group 2 with abuse (0.4%), and 3,426 comparison subjects in Group 3 with alcohol dependence in the absence of a sedative-hypnotic use disorder (36.7%). The remaining COGA subjects (48.5%) were not included as they had neither alcohol nor sedative-hypnotic dependence or abuse. Those with sedative-hypnotic abuse or dependence were more likely to be Caucasian individuals with abuse or dependence on marijuana, cocaine, amphetamines, or opioids. Subjects in Groups 1 and 2 were also more likely to have histories of independent major depressive and panic disorders, as well as substance-induced mood disorders. Those with dependence, compared to abuse, were likely to be women, reported staying intoxicated for a day or more, but noted less abuse of opioids or amphetamines, although Group 2 members also had high rates of difficulties with sedative-hypnotics. These results highlight notable rates of sedative-hypnotic dependence in the COGA families, and indicate that while sedative-hypnotic abuse does occur, and while the clinical course can involve relatively serious problems, it is less common than dependence.