Using cannabis is perceived by many as relatively harmless, but the adverse effects of problematic cannabis use are significant. Thirteen million individuals globally have Cannabis Use Disorders (CUDs; UNODC, 2015), with relapse rates comparable to those of other substance use disorders (~52–70%; Budney et al., 1999; Chauchard et al., 2013). Contrasting non-problematic recreational cannabis use, severe forms of CUD involve compulsive use despite significant harms to mental health; high stress levels (craving, withdrawal); cognitive deficits; academic and work absenteeism; and significant risky behaviors, such as driving and operating machinery while intoxicated. Worryingly, the concentration of Δ9-tetrahydrocannabinol, the compound driving the addiction liability of cannabis, has risen in cannabis products over the past decade (UNODC, 2015).