ABSTRACT. Objective: The purpose of this work was to assess neuropsychological functioning of individuals in early abstinence from methamphetamine dependence and to test for cognitive change over the first month of abstinence. Method: Methamphetamine-dependent subjects in very early abstinence from methamphetamine (4-9 days; n = 27) were compared with healthy comparison subjects (n = 28) on a test battery that evaluated five cognitive domains (attention/processing speed, learning/memory, working memory, timed executive functioning, and untimed executive functioning). A subsample of the methamphetaminedependent subjects (n =18), who maintained abstinence for 1 month, as well as a subsample of the comparison subjects (n = 21), were retested. Results: At the first assessment, the methamphetamine-dependent subjects showed significantly worse performance than the comparison group on a test of processing speed; they also performed 0.31 SDs worse than the control group on a global battery composite score (p < .05). After a month of abstinence, methamphetamine-dependent subjects demonstrated slightly more cognitive improvement than healthy control subjects on the entire cognitive battery, but this difference did not approach statistical significance (p = .33 (Gonzalez et al., 2004(Gonzalez et al., , 2007Hoffman et al., 2006;Kalechstein et al., 2003;Monterosso et al., 2005;Paulus et al., 2003;Salo et al., 2002Salo et al., , 2005Salo et al., , 2007Simon et al., 2000 Simon et al., , 2002Woods et al., 2005). In a meta-analysis of studies comparing individuals with MA abuse or dependence to healthy control subjects (Scott et al., 2007) Despite evidence provided by meta-analytic data, which is collapsed across studies, individual MA-dependent subjects vary in the severity of cognitive deficits they exhibit (Dean and London, 2010), and not all studies of MA-abusing subjects have demonstrated weaknesses. In one study, MA-dependent subjects (n = 44), who were abstinent for a week, did not significantly differ from matched comparison subjects (n = 28) on a battery of motor functioning, verbal memory, attention/processing speed, working memory, reaction time, and executive functioning (Chang et al