Short food supply chains (SFSCs) are often seen as being capable of making a valuable contribution to the provisioning of cities from an environmentally, economically, and socially sustainable perspective. However, there are doubts as to whether these supply chains deserve this reputation. They involve varied needs and logistical challenges for both farmers and cities, and can have equally varied, and sometimes adverse, economic, environmental and social impacts. These challenges and impacts seem also different from one chain to another. This chapter presents a theoretical framework to help understand these diverse challenges and impacts among SFSCs. Using the economics of conventions, we highlight the importance of coordination between production and demand. This framework is applied to SFSCs operating with one intermediary in the French region of Nord – Pas-de–Calais. Our observations show that the need for rapid and frequent deliveries remains important in SFSCs, making them vulnerable to the negative impacts associated with transport intensive flows of products. The management of information flows varies from one chain to another, and some require more complexity and exchanges between actors. The relationships created by these exchanges can have positive social impacts, creating ties between producers and customers. One type of chain appears particularly suited to the creation of sustainable logistic schemes.