Few legislative and regulatory issues in the United States are as polarizing as cannabis, but there is no denying that it is being medically and recreationally legalized in many states. In 2016, nine states had medical and recreational cannabis-related questions on their ballots. Currently, twenty-nine states and the District of Columbia have legalized the medical use of cannabis. Eight states and the District of Columbia have legalized cannabis for recreational use. State and local governments, advocacy groups, medical professionals and consumers are vigorously engaged in conversation on the topic. The 2017 National Cannabis Summit provided an objective national platform for these stakeholders to come together to discuss policies and regulatory approaches to enhance public health and safety, advance research, and improve prevention and treatment to respond to changing cannabis policies.