ABSTRACT. Objective:The diagnostic categories of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, for substance abuse and dependence are commonly used in clinical work and research studies, but whether abuse and dependence represent two different syndromes has been debated. The purpose of this article is to investigate the relationship of substance abuse and dependence for cannabis, cocaine, stimulants and sedatives among lifetime users of these substances in the National Epidemiologic Survey on Alcohol and Related Conditions, a nationally representative survey conducted in [2001][2002]. Method: The multiple indicators multiple causes (MIMIC) model addresses three sets of relationships: those between (1) diagnostic criteria and latent factors, (2) latent factors and covariates, and (3) criteria and covariates. This approach allows for the detection of and compensation for noninvariance of the measurement of criteria across subgroups. Results: Compared with one-factor models, two-factor models (factors roughly corresponding to abuse and dependence) fi t signifi cantly better across all substances, with abuse and dependence factors highly correlated. The MIMIC model indicated that race/ethnicity, age, income, and marital status showed some differential relationships across substance groups, although most covariates showed similar associations to dependence and abuse factors. Noninvariance of criteria measurement by demographic covariates was most pronounced for cannabis abuse and dependence criteria. Conclusions: The general relationship of abuse to dependence was consistent across substances. Results were equivocal on the value of retaining separate factors; therefore, investigating the relationships of specifi c genetic variants and treatment outcomes to dimensional indicators of abuse, dependence, and measures combining these criteria is warranted. Measurement of cannabis abuse and dependence criteria appears most affected by demographic characteristics. (J. Stud. Alcohol Drugs, 73, 368-378, 2012 Disorders, Fourth Edition (DSM-IV; American Psychiatric Association, 1994), are based on the concept of the alcohol dependence syndrome (Edwards, 1986;Edwards and Gross, 1976), generalized to drugs in 1981(Edwards et al., 1981. Dependence was considered to be a combination of physiological and psychological processes leading to increasingly impaired control over substance use even in the face of negative consequences. This syndrome was viewed as one "axis" of substance problems, with the consequences of heavy use (social, legal, and medical problems; hazardous use) considered a separate axis. This bi-axial characterization (Edwards, 1986) led to the DSM-IV distinction (American Psychiatric Association, 1994) between abuse (mainly social, role functioning, or legal problems or hazardous use, most commonly driving while intoxicated) and dependence criteria (tolerance, withdrawal, and numerous indicators of impaired control over use).The concepts of DSM-IV substance abuse and dependence are ...