Among the time-reference forms of English, the acquisition of the present perfect is regarded as the single most challenging task for non-native speakers, mainly due to the semantic peculiarities of this form in contrast to many other languages. In this chapter, we focus on variation between the present perfect and the simple past in German-speaking learners to assess the influence of learner proficiency level and mode on the use of the present perfect. Our results suggest that (i) the present perfect is more frequent in writing, and (ii) emerges very late in learner language, such that only the most advanced learners, and specifically those who started learning English very early in primary school, use it as frequently as native speakers. This finding tentatively supports proponents of early English language teaching. To explain the results, we explore potential reasons for the late emergence of the present perfect, and conclude with specific recommendations for English language teaching.