International studies, such as the "Programme for International Student Assessment" (PISA), have shown that, in most participating countries, students who do not typically speak the test language at home reach lower levels of reading comprehension than students using the test language at home (Stanat & Christensen, "2006"). Results from PISA indicate that Germany is among the countries with the most pronounced differences in reading comprehension between immigrant students and students from native families. The present article summarizes these findings and shows that the reading achievement gap persists even when the socioeconomic and educational background of students' families are controlled. Furthermore, although controlling for background factors reduces the effect of the language spoken at home on reading, it continues to be substantial. Using these findings as a starting point, the article addresses the question of what should be done to close this gap. It summarizes research findings indicating that oral proficiency presents an important determinant of reading comprehension in a second language. This suggests that effective general approaches to second-language teaching are needed to promote reading literacy in a L2. The article closes with a discussion of the available evidence on the effectiveness of such approaches and outlines the need for further research.