In Austria, segregated German language support classes (GLSC) were introduced in the school year 2018/19 to intensively support students who had previously little or no contact with German, the official language of instruction. These classes have been widely criticised; however, a formal evaluation of their effects has yet to be published. In absence of this evaluation, this article describes the language support model as it currently exists in Austria and reviews existing evidence about its efficacy. The literature review synthesises findings from educational research undertaken in other contexts that offer insight into features of 'good practice' in language support models. The article then explores the extent to which GLSC comply with these features. As such, this review allows insights into ways of ensuring students' language and socio-emotional development -- all central aspects of academic success -- in language support models. It therefore allows research-informed understanding of the effects of the newly implemented model of German support classes in Austria and makes recommendations for further development.