Digestive fistulae have a quite variable clinical presentation, depending on their origin and topography. Even when very small, they can cause considerable mechanical or metabolic derangement. Surgical correction often implies an operation with important consequences. The injection of an occlusive emulsion can, in a certain number of cases, close off the fistulous tract with minimal inconvenience. We have injected several invalidating fistulae between the digestive or respiratory tract and the skin with Ethibloc. Total occlusion of the fistulae was accomplished after one or more injections. The emulsion is resorbed after around 10 days, leaving a scar. The inclusion of radio-opaque material allows intraoperative control of injection. This technique widens the therapeutic modalities applicable to a difficult medical condition. When confronted with advanced inflammatory or neoplastic disease, for example, Ethnibloc injection can be considered if the tissue quality is sufficient. Gross infection or tissue necrosis are, in our experience, relative contraindications; the occlusive emulsion cannot adhere and is rapidly evacuated by the fistula.