In circular horticulture there no longer is any waste, but only residual flows that are reused. Residual flows from other sectors, such as livestock farming, are also used as a raw material in horticulture. These circular chains pose potential risks in the phytosanitary field and in the field of public health. How do you keep track of these chains and how do you manage both phytosanitary and global health risks? What measures must be taken? What can we learn from previous experiences and which technological solutions are possible? In this MeetUp we will look at the next step from a few practical cases.