Following G. Bellmann, the article divides the German loanwords in Czech and Slovak roughly into two groups, namely those lexical units that represent a basic code extension (= type A) and those that are used immediately after adoption as (approximately) synonymous lexical duplicates of already existing designations (= type B). While type A words have the best chances of lasting integration, type B words elicit a competitive situation between old and new designations, which can result in substitution, negative integration or semantic diversification. Furthermore, the paper deals with idiosyncrasies of German loanword integration such as the expressiveness of German loanwords in Czech and Slovak and the emotional attitude towards German loanwords in those languages. The article also discusses the causality of displacement and substitution of German loanwords, subsequently elaborates on the loss of terms and realities, the change in domain-specific language use, the role of language awareness and language culture, the loss of immediate contact areas as well as the question of prestige, and concludes with an outlook on future developments.