Over the last 30 years, major changes on the supply side of cannabis have occurred. The shift to (inter)regional production, trade and domestic production of cannabis has become an irreversible international trend. Belgium has been catching up with this trend: the number of plantations that have been dismantled by the authorities has increased sharply in recent years. Typologies of cannabis cultivators always include large-scale (commercially oriented) growers on the one hand, and small scale cultivators ('home growers' ) on the other, and a grey zone in between ('social-commercial cultivators'). Little is known about the exact market share and role of these different types of cannabis producers. Perhaps the most pressing policy issues relate to the differential harmfulness of activities within each type of cannabis producers, and the differential impact of the Belgian drug policy on different segments and networks of the cannabis production market. This study aims to describe the organization of cannabis production in Belgium, to create typologies of different types of cannabis producers in Belgium and identify their modi operandi and aims; to assess the market significance of different types of cannabis producers in Belgium (i.e. market segments); to estimate the harms associated with different types of producers; and to evaluate the impact of the Belgian drug policy strategies on them. The study is based on two main sets of data: a large-scale anonymous, quantitative web survey among 1.293 Belgian small-scale cannabis producers, and an analysis of 34 criminal proceedings, and qualitative interviews with 32 law enforcement officers and other experts and with 20 imprisoned cannabis producers