Interference from the student's mother-tongue is often underestimated as a cause of language inaccuracies. Outside English-speaking countries, translation is frequently regarded as a useful means of heightening awareness, yet there is still a lot of resistance to any form of translation amount native teachers, not least because of (presumed) practical reasons. While vocational training is clearly to be left to the experts, translation can be used as a useful back-up tool within a communicative approach. Through contrastive analysis, translation can highlight areas where interference occurs and (from time to time) provide practice and control. A number of examples showing the way translation can be exploited by native and non-native teachers in the EFL classroom conclude this short insight into interference and ways of intervening.