The goal was to inform the ongoing dialogue about policy options for the regulation of cannabis in Canada and internationally by observing the effects of the various models and approaches in the two states. [...] The CCSA delegation learned the following key lessons about developing a regulatory framework from stakeholders: Reconcile medical and retail markets to promote consistency in such areas as purchase quantities and administration, and to reduce the scope of the grey market, which is the market for products produced or distributed in ways that are unauthorized or unregulated, but not strictly ille [...] To this end, and in light of ongoing dialogue about the impacts and policy options for the regulation of cannabis1 in Canada and internationally, CCSA coordinated visits with partners to Colorado and Washington state in February and August, 2015, about a year after retail sales of cannabis were implemented in each state. [...] These visits brought senior CCSA leadership and subject-matter experts, and partners from public health, treatment and enforcement to meet with diverse stakeholders to learn from evidence and experience about the health, social, economic and public safety impact of cannabis legalization.2 The purpose of these visits was not to arrive at a position on the question of legalization, but to ensure tha [...] The legalization of cannabis is often promoted as a way to reduce the black market and the role of organized crime, reduce the impact of criminal charges on those apprehended for possession, improve product safety and generate tax revenue.