This report is a review, synthesis, and knowledge management of cannabis control and the impacts of recreational cannabis legislation overseas to serve as basic information for evidence-based policy-making, technical development, and research in Thailand. There are five main questions: 1. What are the current forms of cannabis control in various countries? 2. What are the options and considerations in designing cannabis control measures? 3. What are the impacts of recreational cannabis legalization under the International Drug Control Conventions? 4. What are the impacts of allowing the sale or procurement of recreational cannabis, i.e., “cannabis liberalization policy” among implemented countries? and 5. What are the recommended technical and research actions pertaining to monitoring and evaluation of cannabis policy in Thailand? METHODS Due to the short period of time to produce this review (4 months), the authors started by searching for the most recent systematic reviews, followed by additional original papers to obtain recent data on each issue. The authors used PubMed as the main database to search for the literatures, followed by Google (where applicable). The authors paid more attention to peer-reviewed articles than reports or documents published by a particular group. The authors also tried to assess and select studies with proper methodology, samples that were representative of the state or country-level population, and with a comparison group. Examples include comparison of states with and without cannabis legalization laws, before and after cannabis legislation, quasi-experimental studies, and research work with interrupted time-series analysis. RESULTS Legal measures to control cannabis can be categorized into 5 types: 1. Criminalization of cannabis, including use, distribution, and possession thereof. This is the most common form of control worldwide, particularly in Asian countries such as Afghanistan, Bahrain, Brunei Darussalam, Indonesia, Japan, Iraq, and Malaysia. 2. Designation of cannabis as an illegal but decriminalized substance. This includes imposing a fine for users but without legal penalty. Vendors remain liable for criminal penalty. This form of control is practiced in some Western countries, including Belize, Bolivia, Dominica, Moldova, Paraguay, and Saint Lucia 3. Designation of cannabis as a narcotic with allowance for medical use, such as in Lebanon, Lithuania, New Zealand, North Macedonia, and Norway 4. Decriminalization of cannabis but with strict control of misuse. This form of control includes limitation of possession amount, prohibitions (of sale to youths, advertising, operating vehicles under the influence), and use of cannabis taxation. Countries practicing this form of control include Canada, the United States (in certain states), and Uruguay 5. Decriminalization of cannabis and allowance for free market competition, with free or relatively free ability to cultivate, distribute, or advertise. Currently, there are 47 countries where the laws allow for use of cannabis for legal purposes, 38 countries with depenalization for cannabis possession and use. Options in reduced control of cannabis. Cannabis control under international law. Impact of recreational cannabis policy on health and society. Health and social impacts, Social and economic impacts and Recommendations for development of cannabis policy in Thailand.