Although language attitudes are typically studied among adults, research at the intersection of developmental psychology and sociolinguistics suggests that the capacity to view language as providing social meaning emerges early in development. This chapter provides a developmental overview of research on infants’ and young children’s attention to language and accent as conveying social meaning, and reveals the process by which children begin discriminating languages, forming preferences, and ultimately expressing social attitudes that reflect societal input about linguistic status and stereotypes. Studies of infants rely on non-verbal responses such as looking behaviours. As infants grow into young children, both verbal and non-verbal methods are used to assess children’s preferences, inferences, and attitudes about people who speak in different ways. This chapter introduces different experimental methods that can be used to study infants’ and young children’s language-based social responses, including a discussion of the methods’ strengths and limitations. The chapter addresses key practical issues of planning and research design (e.g. recruitment and sample size) as well as data analysis and interpretation (e.g. how to interpret the meaning of infants’ looking responses). To illustrate these points, the chapter concludes with a case study of American children’s attitudes towards Northern and Southern American English.