HB1, which was enacted in 2012, regulates pain clinics and sets new requirements for prescribers and dispensers of controlled substances (CS), including mandatory registration with the Kentucky All Schedule Prescription Electronic Reporting (KASPER) system and the reporting of CS dispensing records to KASPER within 1 day of dispensing. The evaluation found that the number of prescriptions dispensed for all schedules of CS have decreased by 4-8 percent in the post-HB1 period; however, although both opioid and benzodiazepine prescribing decreased, stimulant prescribing continued to increase at its previous rate. This is not unexpected, since HB1 is designed to address the abuse and diversion of Schedule II opioid and Schedule III hydrocodone products. Regarding concerns about the "chilling" effects of HB1, a survey of prescribers, pharmacists, and law enforcement agencies indicated that although there was initial confusion and disruption to workflow in their work, these issues have been resolved and have not adversely impacted health-care professional practices; however, the evaluation found that a minority of prescribers no longer prescribe CS or prescribe fewer CS in order to avoid the additional administrative tasks and potential consequences associated with any inadvertent failure to comply with HB1 provisions. The evaluation consisted of three projects. One project studied changes in KASPER use and CS prescribing. A second project conducted a qualitative study that determined user perceptions of the effectiveness of KASPER and identified any unintended consequences of HB1. A third project studied changes in patient and prescriber behavior and outcomes. The evaluation recommends continued analyses of prescribing behavior, patient behavior, and outcomes in the post-HB1 period, so as to determine whether the impacts observed in the first year post-HB1 are sustained. 36 figures and 31 tables