Abstract: CM-based treatments for SUD originate in basic behavioral science, namely the operant conditioning literature. Operant conditioning is a type of learning in which behavior is modified or maintained through the consequences it produces. In the context of SUD treatment, CM typically modifies substance use by delivering tangible, positive reinforcers (eg, prizes, vouchers, or monetary reinforcement) in exchange for evidence of the performance of the targeted behavior, such as the submission of a drug-negative urine sample. Several meta-analyses have found CM to be among the most effective interventions for SUDs, in addition to being effective at promoting treatment retention and medication adherence. Moreover, clinical trials have consistently shown that CM is also a cost-effective technique. Indeed, studies conducted over the past 30 years have found that CM can be used to promote abstinence from substances including cocaine, methamphetamine, tobacco, alcohol, opioids, cannabis, and benzodiazepines. Further, the aforementioned meta-analyses have also found CM to be effective among highly diverse populations, including pregnant women, adolescents, veterans of war, individuals with serious mental illness, unhoused individuals, those from racial and ethnic minority backgrounds, LGBTQ+ community members, and individuals with HIV and hepatitis. Notably, CM’s consistent effects during treatment across diverse trials may be indicative of CM’s ability to improve long-term treatment outcomes, in light of evidence indicating that longer abstinence during treatment is associated with better long-term treatment outcomes.