The book offers a combined discussion of the main theoretical, methodological and application issues related to corpus work. Thus, starting from the definition of what is a corpus and why reading a corpus calls for a different methodology from reading a text, the underlying assumptions behind corpus work are discussed. The two main approaches to corpus work are discussed as the “corpus-based” and the “corpus-driven” approach and the theoretical positions underlying them explored in detail. The book adopts and exemplifies the parameters of the corpus-driven approach and posits a new unit of linguistic description defined systematically in the light of corpus evidence. The applications where the corpus-driven approach is exemplified are language teaching and contrastive linguistics. Alternating between practical examples and theoretical evaluation, the reader is led step-by-step to a detailed understanding of the issues involved in corpus work and, at the same time, tempted to explore for himself some of the major applications where a corpus-driven methodology can reveal unprecedented insights into linguistic patterning.