The book explores the novel field of lexical and conceptual awareness in L2 reading from both a theoretical and an empirical perspective. The theoretical part consists of a thorough literature review of the key terms. The empirical part presents an in-depth analysis of L2 learners’ lexical and conceptual awareness/challenges based on text and worksheet data as well as 110 hours of video material. In total, data from 156 L2 learners participating in video-taped collaborative reading scenarios and the corresponding stimulated recall sessions have been analyzed in a primarily qualitative manner. The results demonstrate the multidimensionality of the two major constructs and highlight learners’ need for further support. Theoretical, methodological and practical recommendations are provided.