The present invention relates to an exhaust system for an internal combustion engine, having an exhaust line for removing exhaust gas from the internal combustion engine and having a secondary fuel supply for introducing secondary fuel into the exhaust gas of the internal combustion engine. To improve the introduction of the secondary fuel into the exhaust, a recirculation device is connected to the exhaust line and to the secondary fuel supply so that the introduction of secondary fuel into the exhaust is accomplished via or through the recirculation device. The recirculation device has a circulation space which receives an exhaust substream from the exhaust line in which the secondary fuel is introduced into the exhaust substream and from which the modified exhaust substream is returned to the exhaust line.