In the context of an international trend of cannabis legalisation and regulation, Switzerland is now allowing strictly supervised local pilot trials of cannabis sales. One of these is the Cann-L project in Lausanne, which will evaluate the impact on cannabis consumption of an access to a non-profit, public health-oriented distribution model. Opening in December 2023, it already has more than 500 participants whose profiles differ from those usually found in population surveys. In addition, around twenty people have already contacted the study's referring doctor, demonstrating a need and interest in advice and support.