Full utilization of prescription drug monitoring programs (PDMPs) can help maximize their potential in addressing prescription drug misuse and diversion and in improving patient care. As more and more PDMPs became operational, health care professionals’ enrollment in the PDMP was discretionary, as was viewing a patient’s prescription history when prescribing or dispensing controlled substances. To increase the use of PDMPs, some states adopted a statutory mandate for practitioners to enroll and use the PDMP under certain circumstances.