In this introductory chapter, the author traces the development of Contrastive Linguistics and Translation Studies over the last decades to the present day, focusing on the role of the computer corpus in giving new impetus to each field and bringing them closer together. She discusses the different types of monolingual and multilingual corpora being used in CL and TS research, proposing at the same time a common corpus terminology. She then relates the contribution of the different corpus types to the major research interests of each discipline, highlighting the complementarity of the research and calling for increased cross-fertilization and resource-pooling. She then examines the practical issues of corpus exploitation, with a review of corpus analysis tools of particular value for CL and TS and finally, the contribution of corpus-based CL and TS research in the teaching of foreign languages and translation.