"Bilingual education programs are a much debated way of integrating immigrant children into the host country's school system. One of the main arguments in favor of bilingual education is its assumed positive effect on the acquisition of the second language and on academic achievement in general. However, the actual scientific evidence on this question is not quite as clear. Evaluation studies in Europe - especially in Germany - are still rare, although some European countries have a long tradition in mother tongue teaching. In contrast, there are numerous studies on North American experiences. However, it is controversial which of them have a methodologically sound basis and what conclusions should be drawn. Questions: What is the effect of bilingual education programs, i.e. the teaching of and through the mother tongue, on L2 acquisition and on the academic achievement of immigrant children? And how large is this effect controlled by and in comparison to other influences, like migration biography, social characteristics of the family, of the social environment and school structures? What forms of bilingual programs and what kinds of evaluation studies have been carried out that address this issue? Which are the ideal and/or minimum methodological standards of evaluation studies, what are common problems and possible solutions? Which groups of students are compared for which reasons? Which differentiations among groups of students and types of programs have to be made when judging the possible effect of such programs? How is 'achievement' measured and what is the reasoning behind the respective operationalization? Which instruments are suitable for measuring academic achievement?" (excerpt). Contents: Robert E. Slavin, Alan Cheung: A synthesis of research on language of reading instruction for English language learners (5-42); Christine H. Rossell, Julia Kuder: Meta-murky: a rebuttal to recent meta-analyses of bilingual education (43-76); Geert Driessen: From cure to curse: the rise and fall of bilingual ...