This study examines the respective influence of three factors on the realization of requests by Japanese EFL learners in high-imposition situations. These three factors were the Length of Stay in an English-Speaking Environment, the use of Syntactic Downgraders and the use of Lexical Downgraders. Request realizations in four different situations on a Discourse Completion Test were judged for appropriacy by a native speaker. These appropriacy scores were compared with each of the three independent variables above. It could be seen that all three factors had a significant effect on the appropriacy of requests. Qualitative analysis of the data, in which the requests of JEFLLs were compared with those of NSs, showed that JEFLLs used a limited range of syntactic downgraders and very few lexical downgraders at all, other than 'please', which was shown to be an ineffective downgrader as compared to other lexical downgraders. Conclusions could be drawn from this, concerning the positive effect of spending an extended period of time (more than three months) in an ESE, and also concerning the need for a greater variety of syntactic and, in particular, lexical downgraders to be included in teaching materials and explicit teacher input in the classroom.