This book is about the use of two languages in everyday life. Bilingualism is a facet of nearly every country in the world and code-switching is a widespread characteristic of bilingual speech. An obvious and at the same time interesting aspect is that bilinguals will, of course, stay within one language when talking to monolinguals. However, when talking to other bilinguals, they will probably use both languages. Thus, in bilingual conversations, they often switch from one language to another and frequently even within an utterance. Such kinds of switches call for a special competence of the two languages involved. But how well the bilinguals have to know each of the languages is a justifiable question. These switches are not arbitrary since they may depend on the situation of the conversation, the topic of the conversation, the emotional aspects involved, the language preference of the speaker and the need to express the own identity. The goal of this book is to look in detail at code-switching in bilingual communication with the help of the present study on Russian-German bilinguals.