When we use language to interact with one another, we become involved in a continuous and dynamic process of exchange. This makes it a fascinating area for behavioral research. During the give-and-take of discourse, the communicators exchange facts, ideas, views, opinions, emotions, and intentions in such a way as to enhance or impede social relationships; create, maintain, and adapt identities; and create or resolve conflicts. In this handbook, distinguished contributors apply the problem-solving perspectives of applied linguistics to answer some fundamental questions: How do our interpersonal relations manifest themselves in language? What is the role of language in developing and maintaining relationships through interpersonal communication? What types of problems occur in interpersonal communication and what kinds of strategies do we use to solve them? How does interpersonal linguistic communication interact with other semiotic modes? The volume is divided into two parts that examine both theoretical and applied topics. Thus, the contributors critically appraise the relevance of applied linguistics to not only understanding but also solving everyday language-related problems.